u32 tpm_get_pub_key_oiap(struct udevice *dev, u32 key_handle,
const void *usage_auth, void *pubkey,
size_t *pubkey_len)
{
const u8 command[14] = {
0x00, 0xc2, /* TPM_TAG */
0x00, 0x00, 0x00, 0x00, /* parameter size */
0x00, 0x00, 0x00, 0x21, /* TPM_COMMAND_CODE */
0x00, 0x00, 0x00, 0x00, /* key handle */
};
const size_t req_size_offset = 2;
const size_t req_key_handle_offset = TPM_REQUEST_HEADER_LENGTH;
const size_t res_pubkey_offset = TPM_RESPONSE_HEADER_LENGTH;
u8 request[sizeof(command) + TPM_REQUEST_AUTH_LENGTH];
u8 response[TPM_RESPONSE_HEADER_LENGTH + TPM_PUBKEY_MAX_LENGTH +
TPM_RESPONSE_AUTH_LENGTH];
size_t response_length = sizeof(response);
u32 err;
if (!oiap_session.valid) {
err = tpm_oiap(dev, NULL);
if (err)
return err;
}
if (pack_byte_string(request, sizeof(request), "sdd",
0, command, sizeof(command),
req_size_offset,
(u32)(sizeof(command)
+ TPM_REQUEST_AUTH_LENGTH),
req_key_handle_offset, key_handle
))
return TPM_LIB_ERROR;
err = create_request_auth(request, sizeof(command), 4, &oiap_session,
request + sizeof(command), usage_auth);
if (err)
return err;
err = tpm_sendrecv_command(dev, request, response, &response_length);
if (err) {
if (err == TPM_AUTHFAIL)
oiap_session.valid = 0;
return err;
}
err = verify_response_auth(0x00000021, response,
response_length - TPM_RESPONSE_AUTH_LENGTH,
0, &oiap_session,
response + response_length -
TPM_RESPONSE_AUTH_LENGTH,
usage_auth);
if (err)
return err;
if (pubkey) {
if ((response_length - TPM_RESPONSE_HEADER_LENGTH
- TPM_RESPONSE_AUTH_LENGTH) > *pubkey_len)
return TPM_LIB_ERROR;
*pubkey_len = response_length - TPM_RESPONSE_HEADER_LENGTH
- TPM_RESPONSE_AUTH_LENGTH;
memcpy(pubkey, response + res_pubkey_offset,
response_length - TPM_RESPONSE_HEADER_LENGTH
- TPM_RESPONSE_AUTH_LENGTH);
}
return 0;
}
static uint32_t _tpm_wrap_unseal(uint32_t locality, const uint8_t *in_data,
uint32_t *secret_size, uint8_t *secret)
{
uint32_t ret;
tpm_nonce_t odd_osap, even_osap;
tpm_nonce_t nonce_even, nonce_odd, nonce_even_d, nonce_odd_d;
tpm_authhandle_t hauth, hauth_d;
tpm_authdata_t shared_secret;
tpm_authdata_t pub_auth, res_auth, pub_auth_d, res_auth_d;
uint8_t cont_session = false, cont_session_d = false;
tpm_key_handle_t hkey = TPM_KH_SRK;
uint32_t offset;
uint32_t ordinal = TPM_ORD_UNSEAL;
tpm_digest_t digest;
/* skip generate nonce for odd_osap, just use the random value in stack */
/* establish a osap session */
ret = tpm_osap(locality, TPM_ET_SRK, TPM_KH_SRK, &odd_osap, &hauth,
&nonce_even, &even_osap);
if ( ret != TPM_SUCCESS )
return ret;
/* calculate the shared secret
shared-secret = HMAC(auth, even_osap || odd_osap) */
offset = 0;
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &even_osap);
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &odd_osap);
HMAC_SHA1((uint8_t *)&srk_authdata, sizeof(srk_authdata),
WRAPPER_IN_BUF, offset,
(uint8_t *)&shared_secret);
/* establish a oiap session */
ret = tpm_oiap(locality, &hauth_d, &nonce_even_d);
if ( ret != TPM_SUCCESS )
return ret;
/* skip generate nonce_odd & nonce_odd_d, just use the random values */
/* calculate authdata */
/* in_param_digest = sha1(1S ~ 6S) */
offset = 0;
UNLOAD_INTEGER(WRAPPER_IN_BUF, offset, ordinal);
UNLOAD_STORED_DATA12(WRAPPER_IN_BUF, offset, in_data);
sha1_buffer(WRAPPER_IN_BUF, offset, (uint8_t *)&digest);
/* authdata1 = hmac(key, in_param_digest || auth_params1) */
offset = 0;
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &digest);
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &nonce_even);
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &nonce_odd);
UNLOAD_INTEGER(WRAPPER_IN_BUF, offset, cont_session);
HMAC_SHA1((uint8_t *)&shared_secret, sizeof(shared_secret),
WRAPPER_IN_BUF, offset,
(uint8_t *)&pub_auth);
/* authdata2 = hmac(key, in_param_digest || auth_params2) */
offset = 0;
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &digest);
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &nonce_even_d);
UNLOAD_BLOB_TYPE(WRAPPER_IN_BUF, offset, &nonce_odd_d);
UNLOAD_INTEGER(WRAPPER_IN_BUF, offset, cont_session_d);
HMAC_SHA1((uint8_t *)&blob_authdata, sizeof(blob_authdata),
WRAPPER_IN_BUF, offset,
(uint8_t *)&pub_auth_d);
/* call the simple seal function */
ret = _tpm_unseal(locality, hkey, in_data,
hauth, &nonce_odd, &cont_session,
(const tpm_authdata_t *)&pub_auth,
hauth_d, &nonce_odd_d, &cont_session_d,
(const tpm_authdata_t *)&pub_auth_d,
secret_size, secret,
&nonce_even, &res_auth, &nonce_even_d, &res_auth_d);
/* skip check for res_auth */
return ret;
}
u32 tpm_load_key2_oiap(struct udevice *dev, u32 parent_handle, const void *key,
size_t key_length, const void *parent_key_usage_auth,
u32 *key_handle)
{
const u8 command[14] = {
0x00, 0xc2, /* TPM_TAG */
0x00, 0x00, 0x00, 0x00, /* parameter size */
0x00, 0x00, 0x00, 0x41, /* TPM_COMMAND_CODE */
0x00, 0x00, 0x00, 0x00, /* parent handle */
};
const size_t req_size_offset = 2;
const size_t req_parent_handle_offset = TPM_REQUEST_HEADER_LENGTH;
const size_t req_key_offset = TPM_REQUEST_HEADER_LENGTH + 4;
const size_t res_handle_offset = TPM_RESPONSE_HEADER_LENGTH;
u8 request[sizeof(command) + TPM_KEY12_MAX_LENGTH +
TPM_REQUEST_AUTH_LENGTH];
u8 response[COMMAND_BUFFER_SIZE];
size_t response_length = sizeof(response);
u32 err;
if (!oiap_session.valid) {
err = tpm_oiap(dev, NULL);
if (err)
return err;
}
if (pack_byte_string(request, sizeof(request), "sdds",
0, command, sizeof(command),
req_size_offset,
sizeof(command) + key_length
+ TPM_REQUEST_AUTH_LENGTH,
req_parent_handle_offset, parent_handle,
req_key_offset, key, key_length
))
return TPM_LIB_ERROR;
err = create_request_auth(request, sizeof(command) + key_length, 4,
&oiap_session,
request + sizeof(command) + key_length,
parent_key_usage_auth);
if (err)
return err;
err = tpm_sendrecv_command(dev, request, response, &response_length);
if (err) {
if (err == TPM_AUTHFAIL)
oiap_session.valid = 0;
return err;
}
err = verify_response_auth(0x00000041, response,
response_length - TPM_RESPONSE_AUTH_LENGTH,
4, &oiap_session,
response + response_length -
TPM_RESPONSE_AUTH_LENGTH,
parent_key_usage_auth);
if (err)
return err;
if (key_handle) {
if (unpack_byte_string(response, response_length, "d",
res_handle_offset, key_handle))
return TPM_LIB_ERROR;
}
return 0;
}
