feat(bt): migrate mbedtls to PSA APIs

This commit is contained in:
Ashish Sharma
2025-12-18 21:18:58 +08:00
parent b4fea9cccc
commit b0da66f7e1
38 changed files with 986 additions and 790 deletions
+47 -95
View File
@@ -1586,16 +1586,10 @@ void esp_ble_controller_log_dump_all(bool output)
#if CONFIG_BT_LE_SM_LEGACY || CONFIG_BT_LE_SM_SC
#define BLE_SM_KEY_ERR 0x17
#if CONFIG_BT_LE_CRYPTO_STACK_MBEDTLS
#include "mbedtls/aes.h"
#if CONFIG_BT_LE_SM_SC
#include "mbedtls/cipher.h"
#include "mbedtls/entropy.h"
#include "mbedtls/ctr_drbg.h"
#include "mbedtls/cmac.h"
#include "mbedtls/ecdh.h"
#include "mbedtls/ecp.h"
#include "psa/crypto.h"
static mbedtls_ecp_keypair keypair;
#define BLE_PUB_KEY_LEN 65
#endif // CONFIG_BT_LE_SM_SC
#else
@@ -1640,78 +1634,40 @@ int ble_sm_alg_gen_dhkey(const uint8_t *peer_pub_key_x, const uint8_t *peer_pub_
const uint8_t *our_priv_key, uint8_t *out_dhkey)
{
uint8_t dh[32];
uint8_t pk[64];
uint8_t pk[BLE_PUB_KEY_LEN];
uint8_t priv[32];
int rc = BLE_SM_KEY_ERR;
swap_buf(pk, peer_pub_key_x, 32);
swap_buf(&pk[32], peer_pub_key_y, 32);
pk[0] = 0x04; // Uncompressed format for public key
swap_buf(&pk[1], peer_pub_key_x, 32);
swap_buf(&pk[33], peer_pub_key_y, 32);
swap_buf(priv, our_priv_key, 32);
#if CONFIG_BT_LE_CRYPTO_STACK_MBEDTLS
struct mbedtls_ecp_point pt = {0}, Q = {0};
mbedtls_mpi z = {0}, d = {0};
mbedtls_ctr_drbg_context ctr_drbg = {0};
mbedtls_entropy_context entropy = {0};
uint8_t pub[65] = {0};
/* Hardcoded first byte of pub key for MBEDTLS_ECP_PF_UNCOMPRESSED */
pub[0] = 0x04;
memcpy(&pub[1], pk, 64);
/* Initialize the required structures here */
mbedtls_ecp_point_init(&pt);
mbedtls_ecp_point_init(&Q);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_entropy_init(&entropy);
mbedtls_mpi_init(&d);
mbedtls_mpi_init(&z);
/* Below 3 steps are to validate public key on curve secp256r1 */
if (mbedtls_ecp_group_load(&keypair.MBEDTLS_PRIVATE(grp), MBEDTLS_ECP_DP_SECP256R1) != 0) {
psa_key_id_t key_id = 0;
psa_status_t status;
psa_key_attributes_t key_attributes = PSA_KEY_ATTRIBUTES_INIT;
psa_set_key_type(&key_attributes, PSA_KEY_TYPE_ECC_KEY_PAIR(PSA_ECC_FAMILY_SECP_R1));
psa_set_key_bits(&key_attributes, 256);
psa_set_key_algorithm(&key_attributes, PSA_ALG_ECDH);
psa_set_key_usage_flags(&key_attributes, PSA_KEY_USAGE_DERIVE);
status = psa_import_key(&key_attributes, priv, 32, &key_id);
if (status != PSA_SUCCESS) {
goto exit;
}
psa_reset_key_attributes(&key_attributes);
size_t output_len = 0;
status = psa_raw_key_agreement(PSA_ALG_ECDH, key_id, pk, BLE_PUB_KEY_LEN, dh, sizeof(dh), &output_len);
if (status != PSA_SUCCESS) {
goto exit;
}
if (mbedtls_ecp_point_read_binary(&keypair.MBEDTLS_PRIVATE(grp), &pt, pub, 65) != 0) {
goto exit;
}
if (mbedtls_ecp_check_pubkey(&keypair.MBEDTLS_PRIVATE(grp), &pt) != 0) {
goto exit;
}
/* Set PRNG */
if ((rc = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy, NULL, 0)) != 0) {
goto exit;
}
/* Prepare point Q from pub key */
if (mbedtls_ecp_point_read_binary(&keypair.MBEDTLS_PRIVATE(grp), &Q, pub, 65) != 0) {
goto exit;
}
if (mbedtls_mpi_read_binary(&d, priv, 32) != 0) {
goto exit;
}
rc = mbedtls_ecdh_compute_shared(&keypair.MBEDTLS_PRIVATE(grp), &z, &Q, &d,
mbedtls_ctr_drbg_random, &ctr_drbg);
if (rc != 0) {
goto exit;
}
rc = mbedtls_mpi_write_binary(&z, dh, 32);
if (rc != 0) {
if (output_len != 32) {
goto exit;
}
rc = 0;
exit:
mbedtls_ecp_point_free(&pt);
mbedtls_mpi_free(&z);
mbedtls_mpi_free(&d);
mbedtls_ecp_point_free(&Q);
mbedtls_entropy_free(&entropy);
mbedtls_ctr_drbg_free(&ctr_drbg);
if (rc != 0) {
return BLE_SM_KEY_ERR;
}
@@ -1735,42 +1691,38 @@ exit:
static int mbedtls_gen_keypair(uint8_t *public_key, uint8_t *private_key)
{
int rc = BLE_SM_KEY_ERR;
mbedtls_entropy_context entropy = {0};
mbedtls_ctr_drbg_context ctr_drbg = {0};
psa_status_t status;
psa_key_id_t key_id = 0;
psa_key_attributes_t key_attributes = PSA_KEY_ATTRIBUTES_INIT;
psa_algorithm_t alg = PSA_ALG_ECDH;
psa_key_type_t key_type = PSA_KEY_TYPE_ECC_KEY_PAIR(PSA_ECC_FAMILY_SECP_R1);
psa_key_usage_t key_usage = PSA_KEY_USAGE_DERIVE | PSA_KEY_USAGE_EXPORT;
mbedtls_entropy_init(&entropy);
mbedtls_ctr_drbg_init(&ctr_drbg);
mbedtls_ecp_keypair_init(&keypair);
if ((rc = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
NULL, 0)) != 0) {
goto exit;
}
if ((rc = mbedtls_ecp_gen_key(MBEDTLS_ECP_DP_SECP256R1, &keypair,
mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
goto exit;
}
if ((rc = mbedtls_mpi_write_binary(&keypair.MBEDTLS_PRIVATE(d), private_key, 32)) != 0) {
psa_set_key_type(&key_attributes, key_type);
psa_set_key_bits(&key_attributes, 256);
psa_set_key_algorithm(&key_attributes, alg);
psa_set_key_usage_flags(&key_attributes, key_usage);
status = psa_generate_key(&key_attributes, &key_id);
if (status != PSA_SUCCESS) {
goto exit;
}
psa_reset_key_attributes(&key_attributes);
size_t olen = 0;
uint8_t pub[65] = {0};
if ((rc = mbedtls_ecp_point_write_binary(&keypair.MBEDTLS_PRIVATE(grp), &keypair.MBEDTLS_PRIVATE(Q), MBEDTLS_ECP_PF_UNCOMPRESSED,
&olen, pub, 65)) != 0) {
status = psa_export_public_key(key_id, public_key, 65, &olen);
if (status != PSA_SUCCESS || olen != 65) {
goto exit;
}
memcpy(public_key, &pub[1], 64);
status = psa_export_key(key_id, private_key, 32, &olen);
if (status != PSA_SUCCESS || olen != 32) {
goto exit;
}
psa_destroy_key(key_id);
rc = 0;
exit:
mbedtls_ctr_drbg_free(&ctr_drbg);
mbedtls_entropy_free(&entropy);
if (rc != 0) {
mbedtls_ecp_keypair_free(&keypair);
return BLE_SM_KEY_ERR;
}
@@ -1789,7 +1741,7 @@ int ble_sm_alg_gen_key_pair(uint8_t *pub, uint8_t *priv)
swap_buf(&pub[32], &ble_sm_alg_dbg_pub_key[32], 32);
swap_buf(priv, ble_sm_alg_dbg_priv_key, 32);
#else
uint8_t pk[64];
uint8_t pk[BLE_PUB_KEY_LEN];
do {
#if CONFIG_BT_LE_CRYPTO_STACK_MBEDTLS
@@ -1804,8 +1756,8 @@ int ble_sm_alg_gen_key_pair(uint8_t *pub, uint8_t *priv)
/* Make sure generated key isn't debug key. */
} while (memcmp(priv, ble_sm_alg_dbg_priv_key, 32) == 0);
swap_buf(pub, pk, 32);
swap_buf(&pub[32], &pk[32], 32);
swap_buf(pub, &pk[1], 32);
swap_buf(&pub[32], &pk[33], 32);
swap_in_place(priv, 32);
#endif // CONFIG_BT_LE_SM_SC_DEBUG_KEYS
return 0;