[Assignment-7] fixed endianess problems

This commit is contained in:
Sascha Tommasone 2024-07-05 23:02:05 +02:00 committed by saschato
parent 6d966e0b94
commit 20529e2768
3 changed files with 45 additions and 13 deletions

View file

@ -50,9 +50,15 @@
#endif
#ifndef SI_SIZE
#define SI_SIZE 2*SK_SIZE
#define SI_SIZE 2*SK_SIZE// + 8
#endif
#define SWAP_UINT32(x) \
(((x) >> 24) & 0x000000FF) | \
(((x) >> 8) & 0x0000FF00) | \
(((x) << 8) & 0x00FF0000) | \
(((x) << 24) & 0xFF000000)
const sgx_ec256_public_t authorized[2] = {
{
0,
@ -80,6 +86,22 @@ int get_private_key_size() {
return SK_SIZE;
}
static inline void pk_little_to_big(uint8_t *pk) {
uint32_t i, j;
for(i = 0, j = PK_SIZE / 2 - 1; i < j; i++, j--) {
uint8_t tmp = pk[i];
pk[i] = pk[j];
pk[j] = tmp;
}
for(i = PK_SIZE / 2, j = PK_SIZE - 1; i < j; i++, j--) {
uint8_t tmp = pk[i];
pk[i] = pk[j];
pk[j] = tmp;
}
}
static sgx_status_t seal_key_pair(sgx_ec256_private_t *private, sgx_ec256_public_t *public, uint8_t **sealed, uint32_t sealed_size) {
// invalid parameter handling
if((private == NULL) || (public == NULL))
@ -138,7 +160,7 @@ static sgx_status_t unseal_key_pair(const uint8_t *sealed, sgx_ec256_private_t *
return status;
}
sgx_status_t get_public_key(const uint8_t *sealed, uint32_t sealed_size, uint8_t *gx, uint32_t gx_size, uint8_t *gy, uint32_t gy_size) {
sgx_status_t get_public_key(const uint8_t *sealed, uint32_t sealed_size, uint8_t *public_key, uint32_t public_key_size) {
// invalid parameter handling
if((sealed == NULL) || (sealed_size == 0)) {
return SGX_ERROR_INVALID_PARAMETER;
@ -151,10 +173,11 @@ sgx_status_t get_public_key(const uint8_t *sealed, uint32_t sealed_size, uint8_t
return status;
}
// copy public key into return buffers
if((gx != NULL) && (gy != NULL)) {
memcpy(gx, public.gx, SK_SIZE);
memcpy(gy, public.gy, SK_SIZE);
// copy public key into return buffer
// swap endianess
if((public_key != NULL) && (public_key != NULL) && (public_key_size == PK_SIZE)) {
memcpy(public_key, public.gx, SK_SIZE);
pk_little_to_big(public_key);
}
// return success
@ -182,6 +205,7 @@ static sgx_status_t verify_signature(const uint8_t *data, const uint32_t data_si
// verify signature
uint8_t result;
// sgx_ecdsa_verify_hash
sgx_status_t verification_status = sgx_ecdsa_verify(data, data_size, public, ecc_signature, &result, ecc_handle);
// handle failed verification process
@ -194,7 +218,7 @@ static sgx_status_t verify_signature(const uint8_t *data, const uint32_t data_si
return result;
}
sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sealed, uint32_t sealed_size, const uint8_t *public_key, uint32_t public_key_size, uint8_t *signature, uint32_t signature_size) {
sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sealed, uint32_t sealed_size, uint8_t *public_key, uint32_t public_key_size, uint8_t *signature, uint32_t signature_size) {
// invalid parameter handling
if((data == NULL) || (data_size == 0)) {
return SGX_ERROR_INVALID_PARAMETER;
@ -251,10 +275,11 @@ sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sea
// TODO: possible wrong endianess for other programms
// copy signature to return buffer
if((signature == NULL) || (signature_size == 0)) {
if((signature == NULL) || (signature_size != SI_SIZE)) {
sgx_ecc256_close_context(ecc_handle);
return SGX_ERROR_INVALID_PARAMETER;
}
memcpy(signature, ecc_signature.x, SI_SIZE);
// seal the key
@ -262,6 +287,10 @@ sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sea
seal_status = seal_key_pair(&private, &public, &sealed, sealed_size);
}
// export pk
memcpy(public_key, public.gx, PK_SIZE);
pk_little_to_big(public_key);
// close ecc handle and return success
sgx_ecc256_close_context(ecc_handle);
return seal_status;
@ -300,6 +329,9 @@ sgx_status_t verify_firmware(const uint8_t *data, uint32_t data_size, const uint
}
// public key little to big
pk_little_to_big(public_key);
// copy public key into struct
memcpy(public.gx, public_key, PK_SIZE);
} else {

View file

@ -44,8 +44,8 @@ enclave {
public int get_signature_size();
public int get_public_key_size();
public int get_private_key_size();
public sgx_status_t get_public_key([in, size=sealed_size]const uint8_t *sealed, uint32_t sealed_size, [out, size=gx_size]uint8_t *gx, uint32_t gx_size, [out, size=gx_size]uint8_t *gy, uint32_t gy_size);
public sgx_status_t sign_firmware([in, size=data_size]const uint8_t *data, uint32_t data_size, [in, out, size=sealed_size]uint8_t *sealed, uint32_t sealed_size, [in, size=public_key_size]const uint8_t *public_key, uint32_t public_key_size, [in, out, size=signature_size]uint8_t *signature, uint32_t signature_size);
public sgx_status_t get_public_key([in, size=sealed_size]const uint8_t *sealed, uint32_t sealed_size, [out, size=public_key_size]uint8_t *public_key, uint32_t public_key_size);
public sgx_status_t sign_firmware([in, size=data_size]const uint8_t *data, uint32_t data_size, [in, out, size=sealed_size]uint8_t *sealed, uint32_t sealed_size, [in, out, size=public_key_size]uint8_t *public_key, uint32_t public_key_size, [in, out, size=signature_size]uint8_t *signature, uint32_t signature_size);
public sgx_status_t verify_firmware([in, size=data_size]const uint8_t *data, uint32_t data_size, [in, size=sealed_size]const uint8_t *sealed, uint32_t sealed_size, [in, size=public_key_size]const uint8_t *public_key, uint32_t public_key_size, [in, size=signature_size]const uint8_t *signature, uint32_t signature_size);
};

View file

@ -44,8 +44,8 @@ int get_signature_size();
int get_public_key_size();
int get_private_key_size();
sgx_status_t get_public_key(const uint8_t *sealed, const uint32_t sealed_size, uint8_t *gx, uint32_t gx_size, uint8_t *gy, uint32_t gy_size);
sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sealed, uint32_t sealed_size, const uint8_t *public_key, uint32_t public_key_size, uint8_t *signature, uint32_t signature_size);
sgx_status_t get_public_key(const uint8_t *sealed, const uint32_t sealed_size, uint8_t *public_key, uint32_t public_key_size);
sgx_status_t sign_firmware(const uint8_t *data, uint32_t data_size, uint8_t *sealed, uint32_t sealed_size, uint8_t *public_key, uint32_t public_key_size, uint8_t *signature, uint32_t signature_size);
sgx_status_t verify_firmware(const uint8_t *data, uint32_t data_size, const uint8_t *sealed, uint32_t sealed_size, const uint8_t *public_key, uint32_t public_key_size, const uint8_t *signature, uint32_t signature_size);
#endif /* !_ENCLAVE_H_ */