//
// Copyright (C) 2014 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#include "trunks/tpm_utility_impl.h"
#include <base/logging.h>
#include <base/memory/scoped_ptr.h>
#include <base/sha1.h>
#include <base/stl_util.h>
#include <crypto/openssl_util.h>
#include <crypto/secure_hash.h>
#include <crypto/sha2.h>
#include <openssl/aes.h>
#include <openssl/rand.h>
#include "trunks/authorization_delegate.h"
#include "trunks/blob_parser.h"
#include "trunks/error_codes.h"
#include "trunks/hmac_authorization_delegate.h"
#include "trunks/hmac_session.h"
#include "trunks/policy_session.h"
#include "trunks/scoped_key_handle.h"
#include "trunks/tpm_constants.h"
#include "trunks/tpm_state.h"
#include "trunks/trunks_factory.h"
namespace {
const char kPlatformPassword[] = "cros-platform";
const char kWellKnownPassword[] = "cros-password";
const size_t kMaxPasswordLength = 32;
// The below maximum is defined in TPM 2.0 Library Spec Part 2 Section 13.1
const uint32_t kMaxNVSpaceIndex = (1<<24) - 1;
// Returns a serialized representation of the unmodified handle. This is useful
// for predefined handle values, like TPM_RH_OWNER. For details on what types of
// handles use this name formula see Table 3 in the TPM 2.0 Library Spec Part 1
// (Section 16 - Names).
std::string NameFromHandle(trunks::TPM_HANDLE handle) {
std::string name;
trunks::Serialize_TPM_HANDLE(handle, &name);
return name;
}
std::string HashString(const std::string& plaintext,
trunks::TPM_ALG_ID hash_alg) {
switch (hash_alg) {
case trunks::TPM_ALG_SHA1:
return base::SHA1HashString(plaintext);
case trunks::TPM_ALG_SHA256:
return crypto::SHA256HashString(plaintext);
}
NOTREACHED();
return std::string();
}
} // namespace
namespace trunks {
TpmUtilityImpl::TpmUtilityImpl(const TrunksFactory& factory)
: factory_(factory) {
crypto::EnsureOpenSSLInit();
}
TpmUtilityImpl::~TpmUtilityImpl() {
}
TPM_RC TpmUtilityImpl::Startup() {
TPM_RC result = TPM_RC_SUCCESS;
Tpm* tpm = factory_.GetTpm();
result = tpm->StartupSync(TPM_SU_CLEAR, nullptr);
// Ignore TPM_RC_INITIALIZE, that means it was already started.
if (result && result != TPM_RC_INITIALIZE) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
result = tpm->SelfTestSync(YES /* Full test. */, nullptr);
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::Clear() {
TPM_RC result = TPM_RC_SUCCESS;
scoped_ptr<AuthorizationDelegate> password_delegate(
factory_.GetPasswordAuthorization(""));
result = factory_.GetTpm()->ClearSync(TPM_RH_PLATFORM,
NameFromHandle(TPM_RH_PLATFORM),
password_delegate.get());
// If there was an error in the initialization, platform auth is in a bad
// state.
if (result == TPM_RC_AUTH_MISSING) {
scoped_ptr<AuthorizationDelegate> authorization(
factory_.GetPasswordAuthorization(kPlatformPassword));
result = factory_.GetTpm()->ClearSync(TPM_RH_PLATFORM,
NameFromHandle(TPM_RH_PLATFORM),
authorization.get());
}
if (GetFormatOneError(result) == TPM_RC_BAD_AUTH) {
LOG(INFO) << "Clear failed because of BAD_AUTH. This probably means "
<< "that the TPM was already initialized.";
return result;
}
if (result) {
LOG(ERROR) << "Failed to clear the TPM: " << GetErrorString(result);
}
return result;
}
void TpmUtilityImpl::Shutdown() {
TPM_RC return_code = factory_.GetTpm()->ShutdownSync(TPM_SU_CLEAR, nullptr);
if (return_code && return_code != TPM_RC_INITIALIZE) {
// This should not happen, but if it does, there is nothing we can do.
LOG(ERROR) << "Error shutting down: " << GetErrorString(return_code);
}
}
TPM_RC TpmUtilityImpl::InitializeTpm() {
TPM_RC result = TPM_RC_SUCCESS;
scoped_ptr<TpmState> tpm_state(factory_.GetTpmState());
result = tpm_state->Initialize();
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
// Warn about various unexpected conditions.
if (!tpm_state->WasShutdownOrderly()) {
LOG(WARNING) << "WARNING: The last TPM shutdown was not orderly.";
}
if (tpm_state->IsInLockout()) {
LOG(WARNING) << "WARNING: The TPM is currently in lockout.";
}
// We expect the firmware has already locked down the platform hierarchy. If
// it hasn't, do it now.
if (tpm_state->IsPlatformHierarchyEnabled()) {
scoped_ptr<AuthorizationDelegate> empty_password(
factory_.GetPasswordAuthorization(""));
result = SetHierarchyAuthorization(TPM_RH_PLATFORM,
kPlatformPassword,
empty_password.get());
if (GetFormatOneError(result) == TPM_RC_BAD_AUTH) {
// Most likely the platform password has already been set.
result = TPM_RC_SUCCESS;
}
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
result = AllocatePCR(kPlatformPassword);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
scoped_ptr<AuthorizationDelegate> authorization(
factory_.GetPasswordAuthorization(kPlatformPassword));
result = DisablePlatformHierarchy(authorization.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::AllocatePCR(const std::string& platform_password) {
TPM_RC result;
TPMI_YES_NO more_data = YES;
TPMS_CAPABILITY_DATA capability_data;
result = factory_.GetTpm()->GetCapabilitySync(
TPM_CAP_PCRS, 0 /*property (not used)*/, 1 /*property_count*/, &more_data,
&capability_data, nullptr /*authorization_delegate*/);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error querying PCRs: " << GetErrorString(result);
return result;
}
TPML_PCR_SELECTION& existing_pcrs = capability_data.data.assigned_pcr;
bool sha256_needed = true;
std::vector<TPMI_ALG_HASH> pcr_banks_to_remove;
for (uint32_t i = 0; i < existing_pcrs.count; ++i) {
if (existing_pcrs.pcr_selections[i].hash == TPM_ALG_SHA256) {
sha256_needed = false;
} else {
pcr_banks_to_remove.push_back(existing_pcrs.pcr_selections[i].hash);
}
}
if (!sha256_needed && pcr_banks_to_remove.empty()) {
return TPM_RC_SUCCESS;
}
TPML_PCR_SELECTION pcr_allocation;
memset(&pcr_allocation, 0, sizeof(pcr_allocation));
if (sha256_needed) {
pcr_allocation.pcr_selections[pcr_allocation.count].hash = TPM_ALG_SHA256;
pcr_allocation.pcr_selections[pcr_allocation.count].sizeof_select =
PCR_SELECT_MIN;
for (int i = 0; i < PCR_SELECT_MIN; ++i) {
pcr_allocation.pcr_selections[pcr_allocation.count].pcr_select[i] = 0xff;
}
++pcr_allocation.count;
}
for (auto pcr_type : pcr_banks_to_remove) {
pcr_allocation.pcr_selections[pcr_allocation.count].hash = pcr_type;
pcr_allocation.pcr_selections[pcr_allocation.count].sizeof_select =
PCR_SELECT_MAX;
++pcr_allocation.count;
}
scoped_ptr<AuthorizationDelegate> platform_delegate(
factory_.GetPasswordAuthorization(platform_password));
TPMI_YES_NO allocation_success;
uint32_t max_pcr;
uint32_t size_needed;
uint32_t size_available;
result = factory_.GetTpm()->PCR_AllocateSync(TPM_RH_PLATFORM,
NameFromHandle(TPM_RH_PLATFORM),
pcr_allocation,
&allocation_success,
&max_pcr,
&size_needed,
&size_available,
platform_delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error allocating PCRs: " << GetErrorString(result);
return result;
}
if (allocation_success != YES) {
LOG(ERROR) << "PCR allocation unsuccessful.";
return TPM_RC_FAILURE;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::TakeOwnership(const std::string& owner_password,
const std::string& endorsement_password,
const std::string& lockout_password) {
// First we set the storage hierarchy authorization to the well know default
// password.
TPM_RC result = TPM_RC_SUCCESS;
result = SetKnownOwnerPassword(kWellKnownPassword);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error injecting known password: " << GetErrorString(result);
return result;
}
result = CreateStorageRootKeys(kWellKnownPassword);
if (result) {
LOG(ERROR) << "Error creating SRKs: " << GetErrorString(result);
return result;
}
result = CreateSaltingKey(kWellKnownPassword);
if (result) {
LOG(ERROR) << "Error creating salting key: "
<< GetErrorString(result);
return result;
}
scoped_ptr<HmacSession> session = factory_.GetHmacSession();
result = session->StartUnboundSession(true);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error initializing AuthorizationSession: "
<< GetErrorString(result);
return result;
}
scoped_ptr<TpmState> tpm_state(factory_.GetTpmState());
result = tpm_state->Initialize();
session->SetEntityAuthorizationValue("");
session->SetFutureAuthorizationValue(endorsement_password);
if (!tpm_state->IsEndorsementPasswordSet()) {
result = SetHierarchyAuthorization(TPM_RH_ENDORSEMENT,
endorsement_password,
session->GetDelegate());
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
}
session->SetFutureAuthorizationValue(lockout_password);
if (!tpm_state->IsLockoutPasswordSet()) {
result = SetHierarchyAuthorization(TPM_RH_LOCKOUT,
lockout_password,
session->GetDelegate());
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
}
// We take ownership of owner hierarchy last.
session->SetEntityAuthorizationValue(kWellKnownPassword);
session->SetFutureAuthorizationValue(owner_password);
result = SetHierarchyAuthorization(TPM_RH_OWNER,
owner_password,
session->GetDelegate());
if ((GetFormatOneError(result) == TPM_RC_BAD_AUTH) &&
tpm_state->IsOwnerPasswordSet()) {
LOG(WARNING) << "Error changing owner password. This probably because "
<< "ownership is already taken.";
return TPM_RC_SUCCESS;
} else if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error changing owner authorization: "
<< GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::StirRandom(const std::string& entropy_data,
AuthorizationDelegate* delegate) {
std::string digest = crypto::SHA256HashString(entropy_data);
TPM2B_SENSITIVE_DATA random_bytes = Make_TPM2B_SENSITIVE_DATA(digest);
return factory_.GetTpm()->StirRandomSync(random_bytes, delegate);
}
TPM_RC TpmUtilityImpl::GenerateRandom(size_t num_bytes,
AuthorizationDelegate* delegate,
std::string* random_data) {
CHECK(random_data);
size_t bytes_left = num_bytes;
random_data->clear();
TPM_RC rc;
TPM2B_DIGEST digest;
while (bytes_left > 0) {
rc = factory_.GetTpm()->GetRandomSync(bytes_left,
&digest,
delegate);
if (rc) {
LOG(ERROR) << "Error getting random data from tpm.";
return rc;
}
random_data->append(StringFrom_TPM2B_DIGEST(digest));
bytes_left -= digest.size;
}
CHECK_EQ(random_data->size(), num_bytes);
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::ExtendPCR(int pcr_index,
const std::string& extend_data,
AuthorizationDelegate* delegate) {
if (pcr_index < 0 || pcr_index >= IMPLEMENTATION_PCR) {
LOG(ERROR) << "Using a PCR index that isnt implemented.";
return TPM_RC_FAILURE;
}
TPM_HANDLE pcr_handle = HR_PCR + pcr_index;
std::string pcr_name = NameFromHandle(pcr_handle);
TPML_DIGEST_VALUES digests;
digests.count = 1;
digests.digests[0].hash_alg = TPM_ALG_SHA256;
crypto::SHA256HashString(extend_data,
digests.digests[0].digest.sha256,
crypto::kSHA256Length);
return factory_.GetTpm()->PCR_ExtendSync(pcr_handle,
pcr_name,
digests,
delegate);
}
TPM_RC TpmUtilityImpl::ReadPCR(int pcr_index, std::string* pcr_value) {
TPML_PCR_SELECTION pcr_select_in;
uint32_t pcr_update_counter;
TPML_PCR_SELECTION pcr_select_out;
TPML_DIGEST pcr_values;
// This process of selecting pcrs is highlighted in TPM 2.0 Library Spec
// Part 2 (Section 10.5 - PCR structures).
uint8_t pcr_select_index = pcr_index / 8;
uint8_t pcr_select_byte = 1 << (pcr_index % 8);
pcr_select_in.count = 1;
pcr_select_in.pcr_selections[0].hash = TPM_ALG_SHA256;
pcr_select_in.pcr_selections[0].sizeof_select = PCR_SELECT_MIN;
pcr_select_in.pcr_selections[0].pcr_select[pcr_select_index] =
pcr_select_byte;
TPM_RC rc = factory_.GetTpm()->PCR_ReadSync(pcr_select_in,
&pcr_update_counter,
&pcr_select_out,
&pcr_values,
nullptr);
if (rc) {
LOG(INFO) << "Error trying to read a pcr: " << GetErrorString(rc);
return rc;
}
if (pcr_select_out.count != 1 ||
pcr_select_out.pcr_selections[0].sizeof_select <
(pcr_select_index + 1) ||
pcr_select_out.pcr_selections[0].pcr_select[pcr_select_index] !=
pcr_select_byte) {
LOG(ERROR) << "TPM did not return the requested PCR";
return TPM_RC_FAILURE;
}
CHECK_GE(pcr_values.count, 1U);
pcr_value->assign(StringFrom_TPM2B_DIGEST(pcr_values.digests[0]));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::AsymmetricEncrypt(TPM_HANDLE key_handle,
TPM_ALG_ID scheme,
TPM_ALG_ID hash_alg,
const std::string& plaintext,
AuthorizationDelegate* delegate,
std::string* ciphertext) {
TPMT_RSA_DECRYPT in_scheme;
if (hash_alg == TPM_ALG_NULL) {
hash_alg = TPM_ALG_SHA256;
}
if (scheme == TPM_ALG_RSAES) {
in_scheme.scheme = TPM_ALG_RSAES;
} else if (scheme == TPM_ALG_OAEP || scheme == TPM_ALG_NULL) {
in_scheme.scheme = TPM_ALG_OAEP;
in_scheme.details.oaep.hash_alg = hash_alg;
} else {
LOG(ERROR) << "Invalid Signing scheme used.";
return SAPI_RC_BAD_PARAMETER;
}
TPMT_PUBLIC public_area;
TPM_RC result = GetKeyPublicArea(key_handle, &public_area);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error finding public area for: " << key_handle;
return result;
} else if (public_area.type != TPM_ALG_RSA) {
LOG(ERROR) << "Key handle given is not an RSA key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kDecrypt) == 0) {
LOG(ERROR) << "Key handle given is not a decryption key";
return SAPI_RC_BAD_PARAMETER;
}
if ((public_area.object_attributes & kRestricted) != 0) {
LOG(ERROR) << "Cannot use RSAES for encryption with a restricted key";
return SAPI_RC_BAD_PARAMETER;
}
std::string key_name;
result = ComputeKeyName(public_area, &key_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error computing key name for: " << key_handle;
return result;
}
TPM2B_DATA label;
label.size = 0;
TPM2B_PUBLIC_KEY_RSA in_message = Make_TPM2B_PUBLIC_KEY_RSA(plaintext);
TPM2B_PUBLIC_KEY_RSA out_message;
result = factory_.GetTpm()->RSA_EncryptSync(key_handle,
key_name,
in_message,
in_scheme,
label,
&out_message,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error performing RSA encrypt: "
<< GetErrorString(result);
return result;
}
ciphertext->assign(StringFrom_TPM2B_PUBLIC_KEY_RSA(out_message));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::AsymmetricDecrypt(TPM_HANDLE key_handle,
TPM_ALG_ID scheme,
TPM_ALG_ID hash_alg,
const std::string& ciphertext,
AuthorizationDelegate* delegate,
std::string* plaintext) {
TPMT_RSA_DECRYPT in_scheme;
if (hash_alg == TPM_ALG_NULL) {
hash_alg = TPM_ALG_SHA256;
}
if (scheme == TPM_ALG_RSAES) {
in_scheme.scheme = TPM_ALG_RSAES;
} else if (scheme == TPM_ALG_OAEP || scheme == TPM_ALG_NULL) {
in_scheme.scheme = TPM_ALG_OAEP;
in_scheme.details.oaep.hash_alg = hash_alg;
} else {
LOG(ERROR) << "Invalid Signing scheme used.";
return SAPI_RC_BAD_PARAMETER;
}
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
TPMT_PUBLIC public_area;
result = GetKeyPublicArea(key_handle, &public_area);
if (result) {
LOG(ERROR) << "Error finding public area for: " << key_handle;
return result;
} else if (public_area.type != TPM_ALG_RSA) {
LOG(ERROR) << "Key handle given is not an RSA key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kDecrypt) == 0) {
LOG(ERROR) << "Key handle given is not a decryption key";
return SAPI_RC_BAD_PARAMETER;
}
if ((public_area.object_attributes & kRestricted) != 0) {
LOG(ERROR) << "Cannot use RSAES for encryption with a restricted key";
return SAPI_RC_BAD_PARAMETER;
}
std::string key_name;
result = ComputeKeyName(public_area, &key_name);
if (result) {
LOG(ERROR) << "Error computing key name for: " << key_handle;
return result;
}
TPM2B_DATA label;
label.size = 0;
TPM2B_PUBLIC_KEY_RSA in_message = Make_TPM2B_PUBLIC_KEY_RSA(ciphertext);
TPM2B_PUBLIC_KEY_RSA out_message;
result = factory_.GetTpm()->RSA_DecryptSync(key_handle,
key_name,
in_message,
in_scheme,
label,
&out_message,
delegate);
if (result) {
LOG(ERROR) << "Error performing RSA decrypt: "
<< GetErrorString(result);
return result;
}
plaintext->assign(StringFrom_TPM2B_PUBLIC_KEY_RSA(out_message));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::Sign(TPM_HANDLE key_handle,
TPM_ALG_ID scheme,
TPM_ALG_ID hash_alg,
const std::string& plaintext,
AuthorizationDelegate* delegate,
std::string* signature) {
TPMT_SIG_SCHEME in_scheme;
if (hash_alg == TPM_ALG_NULL) {
hash_alg = TPM_ALG_SHA256;
}
if (scheme == TPM_ALG_RSAPSS) {
in_scheme.scheme = TPM_ALG_RSAPSS;
in_scheme.details.rsapss.hash_alg = hash_alg;
} else if (scheme == TPM_ALG_RSASSA || scheme == TPM_ALG_NULL) {
in_scheme.scheme = TPM_ALG_RSASSA;
in_scheme.details.rsassa.hash_alg = hash_alg;
} else {
LOG(ERROR) << "Invalid Signing scheme used.";
return SAPI_RC_BAD_PARAMETER;
}
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
TPMT_PUBLIC public_area;
result = GetKeyPublicArea(key_handle, &public_area);
if (result) {
LOG(ERROR) << "Error finding public area for: " << key_handle;
return result;
} else if (public_area.type != TPM_ALG_RSA) {
LOG(ERROR) << "Key handle given is not an RSA key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kSign) == 0) {
LOG(ERROR) << "Key handle given is not a signging key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kRestricted) != 0) {
LOG(ERROR) << "Key handle references a restricted key";
return SAPI_RC_BAD_PARAMETER;
}
std::string key_name;
result = ComputeKeyName(public_area, &key_name);
if (result) {
LOG(ERROR) << "Error computing key name for: " << key_handle;
return result;
}
std::string digest = HashString(plaintext, hash_alg);
TPM2B_DIGEST tpm_digest = Make_TPM2B_DIGEST(digest);
TPMT_SIGNATURE signature_out;
TPMT_TK_HASHCHECK validation;
validation.tag = TPM_ST_HASHCHECK;
validation.hierarchy = TPM_RH_NULL;
validation.digest.size = 0;
result = factory_.GetTpm()->SignSync(key_handle,
key_name,
tpm_digest,
in_scheme,
validation,
&signature_out,
delegate);
if (result) {
LOG(ERROR) << "Error signing digest: " << GetErrorString(result);
return result;
}
if (scheme == TPM_ALG_RSAPSS) {
signature->resize(signature_out.signature.rsapss.sig.size);
signature->assign(StringFrom_TPM2B_PUBLIC_KEY_RSA(
signature_out.signature.rsapss.sig));
} else {
signature->resize(signature_out.signature.rsassa.sig.size);
signature->assign(StringFrom_TPM2B_PUBLIC_KEY_RSA(
signature_out.signature.rsassa.sig));
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::Verify(TPM_HANDLE key_handle,
TPM_ALG_ID scheme,
TPM_ALG_ID hash_alg,
const std::string& plaintext,
const std::string& signature,
AuthorizationDelegate* delegate) {
TPMT_PUBLIC public_area;
TPM_RC return_code = GetKeyPublicArea(key_handle, &public_area);
if (return_code) {
LOG(ERROR) << "Error finding public area for: " << key_handle;
return return_code;
} else if (public_area.type != TPM_ALG_RSA) {
LOG(ERROR) << "Key handle given is not an RSA key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kSign) == 0) {
LOG(ERROR) << "Key handle given is not a signing key";
return SAPI_RC_BAD_PARAMETER;
} else if ((public_area.object_attributes & kRestricted) != 0) {
LOG(ERROR) << "Cannot use RSAPSS for signing with a restricted key";
return SAPI_RC_BAD_PARAMETER;
}
if (hash_alg == TPM_ALG_NULL) {
hash_alg = TPM_ALG_SHA256;
}
TPMT_SIGNATURE signature_in;
if (scheme == TPM_ALG_RSAPSS) {
signature_in.sig_alg = TPM_ALG_RSAPSS;
signature_in.signature.rsapss.hash = hash_alg;
signature_in.signature.rsapss.sig = Make_TPM2B_PUBLIC_KEY_RSA(signature);
} else if (scheme == TPM_ALG_NULL || scheme == TPM_ALG_RSASSA) {
signature_in.sig_alg = TPM_ALG_RSASSA;
signature_in.signature.rsassa.hash = hash_alg;
signature_in.signature.rsassa.sig = Make_TPM2B_PUBLIC_KEY_RSA(signature);
} else {
LOG(ERROR) << "Invalid scheme used to verify signature.";
return SAPI_RC_BAD_PARAMETER;
}
std::string key_name;
TPMT_TK_VERIFIED verified;
std::string digest = HashString(plaintext, hash_alg);
TPM2B_DIGEST tpm_digest = Make_TPM2B_DIGEST(digest);
return_code = factory_.GetTpm()->VerifySignatureSync(key_handle,
key_name,
tpm_digest,
signature_in,
&verified,
delegate);
if (return_code == TPM_RC_SIGNATURE) {
LOG(WARNING) << "Incorrect signature for given digest.";
return TPM_RC_SIGNATURE;
} else if (return_code && return_code != TPM_RC_SIGNATURE) {
LOG(ERROR) << "Error verifying signature: " << GetErrorString(return_code);
return return_code;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::CertifyCreation(TPM_HANDLE key_handle,
const std::string& creation_blob) {
TPM2B_CREATION_DATA creation_data;
TPM2B_DIGEST creation_hash;
TPMT_TK_CREATION creation_ticket;
if (!factory_.GetBlobParser()->ParseCreationBlob(creation_blob,
&creation_data,
&creation_hash,
&creation_ticket)) {
LOG(ERROR) << "Error parsing CreationBlob.";
return SAPI_RC_BAD_PARAMETER;
}
TPM2B_DATA qualifying_data;
qualifying_data.size = 0;
TPMT_SIG_SCHEME in_scheme;
in_scheme.scheme = TPM_ALG_NULL;
TPM2B_ATTEST certify_info;
TPMT_SIGNATURE signature;
scoped_ptr<AuthorizationDelegate> delegate =
factory_.GetPasswordAuthorization("");
TPM_RC result = factory_.GetTpm()->CertifyCreationSync(TPM_RH_NULL,
"",
key_handle,
"",
qualifying_data,
creation_hash,
in_scheme,
creation_ticket,
&certify_info,
&signature,
delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error certifying key creation: " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::ChangeKeyAuthorizationData(
TPM_HANDLE key_handle,
const std::string& new_password,
AuthorizationDelegate* delegate,
std::string* key_blob) {
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string key_name;
std::string parent_name;
result = GetKeyName(key_handle, &key_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for key_handle: "
<< GetErrorString(result);
return result;
}
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for RSA-SRK: "
<< GetErrorString(result);
return result;
}
TPM2B_AUTH new_auth = Make_TPM2B_DIGEST(new_password);
TPM2B_PRIVATE new_private_data;
new_private_data.size = 0;
result = factory_.GetTpm()->ObjectChangeAuthSync(key_handle,
key_name,
kRSAStorageRootKey,
parent_name,
new_auth,
&new_private_data,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error changing object authorization data: "
<< GetErrorString(result);
return result;
}
if (key_blob) {
TPMT_PUBLIC public_data;
result = GetKeyPublicArea(key_handle, &public_data);
if (result != TPM_RC_SUCCESS) {
return result;
}
if (!factory_.GetBlobParser()->SerializeKeyBlob(
Make_TPM2B_PUBLIC(public_data), new_private_data, key_blob)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::ImportRSAKey(AsymmetricKeyUsage key_type,
const std::string& modulus,
uint32_t public_exponent,
const std::string& prime_factor,
const std::string& password,
AuthorizationDelegate* delegate,
std::string* key_blob) {
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string parent_name;
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for RSA-SRK: "
<< GetErrorString(result);
return result;
}
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_RSA);
public_area.object_attributes = kUserWithAuth | kNoDA;
switch (key_type) {
case AsymmetricKeyUsage::kDecryptKey:
public_area.object_attributes |= kDecrypt;
break;
case AsymmetricKeyUsage::kSignKey:
public_area.object_attributes |= kSign;
break;
case AsymmetricKeyUsage::kDecryptAndSignKey:
public_area.object_attributes |= (kSign | kDecrypt);
break;
}
public_area.parameters.rsa_detail.key_bits = modulus.size() * 8;
public_area.parameters.rsa_detail.exponent = public_exponent;
public_area.unique.rsa = Make_TPM2B_PUBLIC_KEY_RSA(modulus);
TPM2B_DATA encryption_key;
encryption_key.size = kAesKeySize;
CHECK_EQ(RAND_bytes(encryption_key.buffer, encryption_key.size), 1) <<
"Error generating a cryptographically random Aes Key.";
TPM2B_PUBLIC public_data = Make_TPM2B_PUBLIC(public_area);
TPM2B_ENCRYPTED_SECRET in_sym_seed = Make_TPM2B_ENCRYPTED_SECRET("");
TPMT_SYM_DEF_OBJECT symmetric_alg;
symmetric_alg.algorithm = TPM_ALG_AES;
symmetric_alg.key_bits.aes = kAesKeySize * 8;
symmetric_alg.mode.aes = TPM_ALG_CFB;
TPMT_SENSITIVE in_sensitive;
in_sensitive.sensitive_type = TPM_ALG_RSA;
in_sensitive.auth_value = Make_TPM2B_DIGEST(password);
in_sensitive.seed_value = Make_TPM2B_DIGEST("");
in_sensitive.sensitive.rsa = Make_TPM2B_PRIVATE_KEY_RSA(prime_factor);
TPM2B_PRIVATE private_data;
result = EncryptPrivateData(in_sensitive, public_area,
&private_data, &encryption_key);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error creating encrypted private struct: "
<< GetErrorString(result);
return result;
}
TPM2B_PRIVATE tpm_private_data;
tpm_private_data.size = 0;
result = factory_.GetTpm()->ImportSync(kRSAStorageRootKey,
parent_name,
encryption_key,
public_data,
private_data,
in_sym_seed,
symmetric_alg,
&tpm_private_data,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error importing key: " << GetErrorString(result);
return result;
}
if (key_blob) {
if (!factory_.GetBlobParser()->SerializeKeyBlob(
public_data, tpm_private_data, key_blob)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::CreateRSAKeyPair(AsymmetricKeyUsage key_type,
int modulus_bits,
uint32_t public_exponent,
const std::string& password,
const std::string& policy_digest,
bool use_only_policy_authorization,
int creation_pcr_index,
AuthorizationDelegate* delegate,
std::string* key_blob,
std::string* creation_blob) {
CHECK(key_blob);
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string parent_name;
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for RSA-SRK: "
<< GetErrorString(result);
return result;
}
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_RSA);
public_area.auth_policy = Make_TPM2B_DIGEST(policy_digest);
public_area.object_attributes |=
(kSensitiveDataOrigin | kUserWithAuth | kNoDA);
switch (key_type) {
case AsymmetricKeyUsage::kDecryptKey:
public_area.object_attributes |= kDecrypt;
break;
case AsymmetricKeyUsage::kSignKey:
public_area.object_attributes |= kSign;
break;
case AsymmetricKeyUsage::kDecryptAndSignKey:
public_area.object_attributes |= (kSign | kDecrypt);
break;
}
if (use_only_policy_authorization && !policy_digest.empty()) {
public_area.object_attributes |= kAdminWithPolicy;
public_area.object_attributes &= (~kUserWithAuth);
}
public_area.parameters.rsa_detail.key_bits = modulus_bits;
public_area.parameters.rsa_detail.exponent = public_exponent;
TPML_PCR_SELECTION creation_pcrs = {};
if (creation_pcr_index == kNoCreationPCR) {
creation_pcrs.count = 0;
} else if (creation_pcr_index < 0 ||
creation_pcr_index > (PCR_SELECT_MIN * 8)) {
LOG(ERROR) << "Creation PCR index is not within the allocated bank.";
return SAPI_RC_BAD_PARAMETER;
} else {
creation_pcrs.count = 1;
creation_pcrs.pcr_selections[0].hash = TPM_ALG_SHA256;
creation_pcrs.pcr_selections[0].sizeof_select = PCR_SELECT_MIN;
creation_pcrs.pcr_selections[0].pcr_select[creation_pcr_index / 8] =
1 << (creation_pcr_index % 8);
}
TPMS_SENSITIVE_CREATE sensitive;
sensitive.user_auth = Make_TPM2B_DIGEST(password);
sensitive.data = Make_TPM2B_SENSITIVE_DATA("");
TPM2B_SENSITIVE_CREATE sensitive_create = Make_TPM2B_SENSITIVE_CREATE(
sensitive);
TPM2B_DATA outside_info = Make_TPM2B_DATA("");
TPM2B_PUBLIC out_public;
out_public.size = 0;
TPM2B_PRIVATE out_private;
out_private.size = 0;
TPM2B_CREATION_DATA creation_data;
TPM2B_DIGEST creation_hash;
TPMT_TK_CREATION creation_ticket;
result = factory_.GetTpm()->CreateSync(kRSAStorageRootKey,
parent_name,
sensitive_create,
Make_TPM2B_PUBLIC(public_area),
outside_info,
creation_pcrs,
&out_private,
&out_public,
&creation_data,
&creation_hash,
&creation_ticket,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error creating RSA key: " << GetErrorString(result);
return result;
}
if (!factory_.GetBlobParser()->SerializeKeyBlob(
out_public, out_private, key_blob)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
if (creation_blob) {
if (!factory_.GetBlobParser()->SerializeCreationBlob(
creation_data, creation_hash, creation_ticket, creation_blob)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::LoadKey(const std::string& key_blob,
AuthorizationDelegate* delegate,
TPM_HANDLE* key_handle) {
CHECK(key_handle);
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string parent_name;
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting parent key name: " << GetErrorString(result);
return result;
}
TPM2B_PUBLIC in_public;
TPM2B_PRIVATE in_private;
if (!factory_.GetBlobParser()->ParseKeyBlob(
key_blob, &in_public, &in_private)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
TPM2B_NAME key_name;
key_name.size = 0;
result = factory_.GetTpm()->LoadSync(kRSAStorageRootKey,
parent_name,
in_private,
in_public,
key_handle,
&key_name,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error loading key: " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::GetKeyName(TPM_HANDLE handle, std::string* name) {
CHECK(name);
TPM_RC result;
TPMT_PUBLIC public_data;
result = GetKeyPublicArea(handle, &public_data);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error fetching public info: " << GetErrorString(result);
return result;
}
result = ComputeKeyName(public_data, name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error computing key name: " << GetErrorString(result);
return TPM_RC_SUCCESS;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::GetKeyPublicArea(TPM_HANDLE handle,
TPMT_PUBLIC* public_data) {
CHECK(public_data);
TPM2B_NAME out_name;
TPM2B_PUBLIC public_area;
TPM2B_NAME qualified_name;
std::string handle_name; // Unused
TPM_RC return_code = factory_.GetTpm()->ReadPublicSync(handle,
handle_name,
&public_area,
&out_name,
&qualified_name,
nullptr);
if (return_code) {
LOG(ERROR) << "Error getting public area for object: " << handle;
return return_code;
}
*public_data = public_area.public_area;
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::SealData(const std::string& data_to_seal,
const std::string& policy_digest,
AuthorizationDelegate* delegate,
std::string* sealed_data) {
CHECK(sealed_data);
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string parent_name;
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for RSA-SRK: "
<< GetErrorString(result);
return result;
}
// We seal data to the TPM by creating a KEYEDHASH object with sign and
// decrypt attributes disabled.
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_KEYEDHASH);
public_area.auth_policy = Make_TPM2B_DIGEST(policy_digest);
public_area.object_attributes = kAdminWithPolicy | kNoDA;
public_area.unique.keyed_hash.size = 0;
TPML_PCR_SELECTION creation_pcrs = {};
TPMS_SENSITIVE_CREATE sensitive;
sensitive.user_auth = Make_TPM2B_DIGEST("");
sensitive.data = Make_TPM2B_SENSITIVE_DATA(data_to_seal);
TPM2B_SENSITIVE_CREATE sensitive_create = Make_TPM2B_SENSITIVE_CREATE(
sensitive);
TPM2B_DATA outside_info = Make_TPM2B_DATA("");
TPM2B_PUBLIC out_public;
out_public.size = 0;
TPM2B_PRIVATE out_private;
out_private.size = 0;
TPM2B_CREATION_DATA creation_data;
TPM2B_DIGEST creation_hash;
TPMT_TK_CREATION creation_ticket;
result = factory_.GetTpm()->CreateSync(kRSAStorageRootKey,
parent_name,
sensitive_create,
Make_TPM2B_PUBLIC(public_area),
outside_info,
creation_pcrs,
&out_private,
&out_public,
&creation_data,
&creation_hash,
&creation_ticket,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error creating sealed object: " << GetErrorString(result);
return result;
}
if (!factory_.GetBlobParser()->SerializeKeyBlob(
out_public, out_private, sealed_data)) {
return SAPI_RC_BAD_TCTI_STRUCTURE;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::UnsealData(const std::string& sealed_data,
AuthorizationDelegate* delegate,
std::string* unsealed_data) {
CHECK(unsealed_data);
TPM_RC result;
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
TPM_HANDLE object_handle;
scoped_ptr<AuthorizationDelegate> password_delegate =
factory_.GetPasswordAuthorization("");
result = LoadKey(sealed_data, password_delegate.get(), &object_handle);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error loading sealed object: " << GetErrorString(result);
return result;
}
ScopedKeyHandle sealed_object(factory_, object_handle);
std::string object_name;
result = GetKeyName(sealed_object.get(), &object_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting object name: " << GetErrorString(result);
return result;
}
TPM2B_SENSITIVE_DATA out_data;
result = factory_.GetTpm()->UnsealSync(sealed_object.get(), object_name,
&out_data, delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error unsealing object: " << GetErrorString(result);
return result;
}
*unsealed_data = StringFrom_TPM2B_SENSITIVE_DATA(out_data);
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::StartSession(HmacSession* session) {
TPM_RC result = session->StartUnboundSession(true /* enable_encryption */);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error starting unbound session: " << GetErrorString(result);
return result;
}
session->SetEntityAuthorizationValue("");
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::GetPolicyDigestForPcrValue(int pcr_index,
const std::string& pcr_value,
std::string* policy_digest) {
CHECK(policy_digest);
scoped_ptr<PolicySession> session = factory_.GetTrialSession();
TPM_RC result = session->StartUnboundSession(false);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error starting unbound trial session: "
<< GetErrorString(result);
return result;
}
std::string mutable_pcr_value;
if (pcr_value.empty()) {
result = ReadPCR(pcr_index, &mutable_pcr_value);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error reading pcr_value: " << GetErrorString(result);
return result;
}
} else {
mutable_pcr_value = pcr_value;
}
result = session->PolicyPCR(pcr_index, mutable_pcr_value);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error restricting policy to PCR value: "
<< GetErrorString(result);
return result;
}
result = session->GetDigest(policy_digest);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting policy digest: " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::DefineNVSpace(uint32_t index,
size_t num_bytes,
AuthorizationDelegate* delegate) {
TPM_RC result;
if (num_bytes > MAX_NV_INDEX_SIZE) {
result = SAPI_RC_BAD_SIZE;
LOG(ERROR) << "Cannot define non-volatile space of given size: "
<< GetErrorString(result);
return result;
}
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot define non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
uint32_t nv_index = NV_INDEX_FIRST + index;
TPMS_NV_PUBLIC public_data;
public_data.nv_index = nv_index;
public_data.name_alg = TPM_ALG_SHA256;
// We define the following attributes for NVSpaces created:
// TPMA_NV_NO_DA: Dictionary attack does not trigger on authorization errors.
// TPMA_NV_OWNERWRITE: Owner authorization must be provided on write actions.
// TPMA_NV_WRITEDEFINE: NVSpace is write lockable, and lock persists across
// reboot.
// TPMA_NV_AUTHREAD: The index authValue (default: "") can be used to
// authorize read actions.
public_data.attributes = TPMA_NV_NO_DA |
TPMA_NV_OWNERWRITE |
TPMA_NV_WRITEDEFINE |
TPMA_NV_AUTHREAD;
public_data.auth_policy = Make_TPM2B_DIGEST("");
public_data.data_size = num_bytes;
TPM2B_AUTH authorization = Make_TPM2B_DIGEST("");
TPM2B_NV_PUBLIC public_area = Make_TPM2B_NV_PUBLIC(public_data);
result = factory_.GetTpm()->NV_DefineSpaceSync(
TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
authorization,
public_area,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error defining non-volatile space: "
<< GetErrorString(result);
return result;
}
nvram_public_area_map_[index] = public_data;
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::DestroyNVSpace(uint32_t index,
AuthorizationDelegate* delegate) {
TPM_RC result;
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot undefine non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string nv_name;
result = GetNVSpaceName(index, &nv_name);
if (result != TPM_RC_SUCCESS) {
return result;
}
uint32_t nv_index = NV_INDEX_FIRST + index;
result = factory_.GetTpm()->NV_UndefineSpaceSync(
TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
nv_index,
nv_name,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error undefining non-volatile space: "
<< GetErrorString(result);
return result;
}
nvram_public_area_map_.erase(index);
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::LockNVSpace(uint32_t index,
AuthorizationDelegate* delegate) {
TPM_RC result;
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot lock non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string nv_name;
result = GetNVSpaceName(index, &nv_name);
if (result != TPM_RC_SUCCESS) {
return result;
}
uint32_t nv_index = NV_INDEX_FIRST + index;
result = factory_.GetTpm()->NV_WriteLockSync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
nv_index,
nv_name,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error locking non-volatile spaces: "
<< GetErrorString(result);
return result;
}
auto it = nvram_public_area_map_.find(index);
if (it != nvram_public_area_map_.end()) {
it->second.attributes |= TPMA_NV_WRITELOCKED;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::WriteNVSpace(uint32_t index,
uint32_t offset,
const std::string& nvram_data,
AuthorizationDelegate* delegate) {
TPM_RC result;
if (nvram_data.size() > MAX_NV_BUFFER_SIZE) {
result = SAPI_RC_BAD_SIZE;
LOG(ERROR) << "Insufficient buffer for non-volatile write: "
<< GetErrorString(result);
return result;
}
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot write to non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string nv_name;
result = GetNVSpaceName(index, &nv_name);
if (result != TPM_RC_SUCCESS) {
return result;
}
uint32_t nv_index = NV_INDEX_FIRST + index;
result = factory_.GetTpm()->NV_WriteSync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
nv_index,
nv_name,
Make_TPM2B_MAX_NV_BUFFER(nvram_data),
offset,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error writing to non-volatile space: "
<< GetErrorString(result);
return result;
}
auto it = nvram_public_area_map_.find(index);
if (it != nvram_public_area_map_.end()) {
it->second.attributes |= TPMA_NV_WRITTEN;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::ReadNVSpace(uint32_t index,
uint32_t offset,
size_t num_bytes,
std::string* nvram_data,
AuthorizationDelegate* delegate) {
TPM_RC result;
if (num_bytes > MAX_NV_BUFFER_SIZE) {
result = SAPI_RC_BAD_SIZE;
LOG(ERROR) << "Insufficient buffer for non-volatile read: "
<< GetErrorString(result);
return result;
}
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot read from non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
if (delegate == nullptr) {
result = SAPI_RC_INVALID_SESSIONS;
LOG(ERROR) << "This method needs a valid authorization delegate: "
<< GetErrorString(result);
return result;
}
std::string nv_name;
result = GetNVSpaceName(index, &nv_name);
if (result != TPM_RC_SUCCESS) {
return result;
}
uint32_t nv_index = NV_INDEX_FIRST + index;
TPM2B_MAX_NV_BUFFER data_buffer;
data_buffer.size = 0;
result = factory_.GetTpm()->NV_ReadSync(nv_index,
nv_name,
nv_index,
nv_name,
num_bytes,
offset,
&data_buffer,
delegate);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error reading from non-volatile space: "
<< GetErrorString(result);
return result;
}
nvram_data->assign(StringFrom_TPM2B_MAX_NV_BUFFER(data_buffer));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::GetNVSpaceName(uint32_t index, std::string* name) {
TPM_RC result;
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot read from non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
TPMS_NV_PUBLIC nv_public_data;
result = GetNVSpacePublicArea(index, &nv_public_data);
if (result != TPM_RC_SUCCESS) {
return result;
}
result = ComputeNVSpaceName(nv_public_data, name);
if (result != TPM_RC_SUCCESS) {
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::GetNVSpacePublicArea(uint32_t index,
TPMS_NV_PUBLIC* public_data) {
TPM_RC result;
if (index > kMaxNVSpaceIndex) {
result = SAPI_RC_BAD_PARAMETER;
LOG(ERROR) << "Cannot read from non-volatile space with the given index: "
<< GetErrorString(result);
return result;
}
auto it = nvram_public_area_map_.find(index);
if (it != nvram_public_area_map_.end()) {
*public_data = it->second;
return TPM_RC_SUCCESS;
}
TPM2B_NAME nvram_name;
TPM2B_NV_PUBLIC public_area;
public_area.nv_public.nv_index = 0;
uint32_t nv_index = NV_INDEX_FIRST + index;
result = factory_.GetTpm()->NV_ReadPublicSync(nv_index,
"",
&public_area,
&nvram_name,
nullptr);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error reading non-volatile space public information: "
<< GetErrorString(result);
return result;
}
*public_data = public_area.nv_public;
nvram_public_area_map_[index] = public_area.nv_public;
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::SetKnownOwnerPassword(
const std::string& known_owner_password) {
scoped_ptr<TpmState> tpm_state(factory_.GetTpmState());
TPM_RC result = tpm_state->Initialize();
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
scoped_ptr<AuthorizationDelegate> delegate =
factory_.GetPasswordAuthorization("");
if (tpm_state->IsOwnerPasswordSet()) {
LOG(INFO) << "Owner password is already set. "
<< "This is normal if ownership is already taken.";
return TPM_RC_SUCCESS;
}
result = SetHierarchyAuthorization(TPM_RH_OWNER,
known_owner_password,
delegate.get());
if (result) {
LOG(ERROR) << "Error setting storage hierarchy authorization "
<< "to its default value: " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::CreateStorageRootKeys(
const std::string& owner_password) {
TPM_RC result = TPM_RC_SUCCESS;
scoped_ptr<TpmState> tpm_state(factory_.GetTpmState());
result = tpm_state->Initialize();
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
Tpm* tpm = factory_.GetTpm();
TPML_PCR_SELECTION creation_pcrs;
creation_pcrs.count = 0;
TPMS_SENSITIVE_CREATE sensitive;
sensitive.user_auth = Make_TPM2B_DIGEST("");
sensitive.data = Make_TPM2B_SENSITIVE_DATA("");
TPM_HANDLE object_handle;
TPM2B_CREATION_DATA creation_data;
TPM2B_DIGEST creation_digest;
TPMT_TK_CREATION creation_ticket;
TPM2B_NAME object_name;
object_name.size = 0;
scoped_ptr<AuthorizationDelegate> delegate =
factory_.GetPasswordAuthorization(owner_password);
if (tpm_state->IsRSASupported()) {
bool exists = false;
result = DoesPersistentKeyExist(kRSAStorageRootKey, &exists);
if (result) {
return result;
}
if (!exists) {
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_RSA);
public_area.object_attributes |=
(kSensitiveDataOrigin | kUserWithAuth | kNoDA |
kRestricted | kDecrypt);
public_area.parameters.rsa_detail.symmetric.algorithm = TPM_ALG_AES;
public_area.parameters.rsa_detail.symmetric.key_bits.aes = 128;
public_area.parameters.rsa_detail.symmetric.mode.aes = TPM_ALG_CFB;
TPM2B_PUBLIC rsa_public_area = Make_TPM2B_PUBLIC(public_area);
result = tpm->CreatePrimarySync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
Make_TPM2B_SENSITIVE_CREATE(sensitive),
rsa_public_area,
Make_TPM2B_DATA(""),
creation_pcrs,
&object_handle,
&rsa_public_area,
&creation_data,
&creation_digest,
&creation_ticket,
&object_name,
delegate.get());
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
ScopedKeyHandle rsa_key(factory_, object_handle);
// This will make the key persistent.
result = tpm->EvictControlSync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
object_handle,
StringFrom_TPM2B_NAME(object_name),
kRSAStorageRootKey,
delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
LOG(INFO) << "Created RSA SRK.";
} else {
LOG(INFO) << "Skip RSA SRK because it already exists.";
}
} else {
LOG(INFO) << "Skip RSA SRK because RSA is not supported.";
}
// Do it again for ECC.
if (tpm_state->IsRSASupported()) {
bool exists = false;
result = DoesPersistentKeyExist(kECCStorageRootKey, &exists);
if (result) {
return result;
}
if (!exists) {
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_ECC);
public_area.object_attributes |=
(kSensitiveDataOrigin | kUserWithAuth | kNoDA |
kRestricted | kDecrypt);
public_area.parameters.ecc_detail.symmetric.algorithm = TPM_ALG_AES;
public_area.parameters.ecc_detail.symmetric.key_bits.aes = 128;
public_area.parameters.ecc_detail.symmetric.mode.aes = TPM_ALG_CFB;
TPM2B_PUBLIC ecc_public_area = Make_TPM2B_PUBLIC(public_area);
result = tpm->CreatePrimarySync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
Make_TPM2B_SENSITIVE_CREATE(sensitive),
ecc_public_area,
Make_TPM2B_DATA(""),
creation_pcrs,
&object_handle,
&ecc_public_area,
&creation_data,
&creation_digest,
&creation_ticket,
&object_name,
delegate.get());
if (result) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
ScopedKeyHandle ecc_key(factory_, object_handle);
// This will make the key persistent.
result = tpm->EvictControlSync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
object_handle,
StringFrom_TPM2B_NAME(object_name),
kECCStorageRootKey,
delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
LOG(INFO) << "Created ECC SRK.";
} else {
LOG(INFO) << "Skip ECC SRK because it already exists.";
}
} else {
LOG(INFO) << "Skip ECC SRK because ECC is not supported.";
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::CreateSaltingKey(const std::string& owner_password) {
bool exists = false;
TPM_RC result = DoesPersistentKeyExist(kSaltingKey, &exists);
if (result != TPM_RC_SUCCESS) {
return result;
}
if (exists) {
LOG(INFO) << "Salting key already exists.";
return TPM_RC_SUCCESS;
}
std::string parent_name;
result = GetKeyName(kRSAStorageRootKey, &parent_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error getting Key name for RSA-SRK: "
<< GetErrorString(result);
return result;
}
TPMT_PUBLIC public_area = CreateDefaultPublicArea(TPM_ALG_RSA);
public_area.name_alg = TPM_ALG_SHA256;
public_area.object_attributes |=
kSensitiveDataOrigin | kUserWithAuth | kNoDA | kDecrypt;
TPML_PCR_SELECTION creation_pcrs;
creation_pcrs.count = 0;
TPMS_SENSITIVE_CREATE sensitive;
sensitive.user_auth = Make_TPM2B_DIGEST("");
sensitive.data = Make_TPM2B_SENSITIVE_DATA("");
TPM2B_SENSITIVE_CREATE sensitive_create = Make_TPM2B_SENSITIVE_CREATE(
sensitive);
TPM2B_DATA outside_info = Make_TPM2B_DATA("");
TPM2B_PRIVATE out_private;
out_private.size = 0;
TPM2B_PUBLIC out_public;
out_public.size = 0;
TPM2B_CREATION_DATA creation_data;
TPM2B_DIGEST creation_hash;
TPMT_TK_CREATION creation_ticket;
// TODO(usanghi): MITM vulnerability with SaltingKey creation.
// Currently we cannot verify the key returned by the TPM.
// crbug.com/442331
scoped_ptr<AuthorizationDelegate> delegate =
factory_.GetPasswordAuthorization("");
result = factory_.GetTpm()->CreateSync(kRSAStorageRootKey,
parent_name,
sensitive_create,
Make_TPM2B_PUBLIC(public_area),
outside_info,
creation_pcrs,
&out_private,
&out_public,
&creation_data,
&creation_hash,
&creation_ticket,
delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error creating salting key: " << GetErrorString(result);
return result;
}
TPM2B_NAME key_name;
key_name.size = 0;
TPM_HANDLE key_handle;
result = factory_.GetTpm()->LoadSync(kRSAStorageRootKey,
parent_name,
out_private,
out_public,
&key_handle,
&key_name,
delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error loading salting key: " << GetErrorString(result);
return result;
}
ScopedKeyHandle key(factory_, key_handle);
scoped_ptr<AuthorizationDelegate> owner_delegate =
factory_.GetPasswordAuthorization(owner_password);
result = factory_.GetTpm()->EvictControlSync(TPM_RH_OWNER,
NameFromHandle(TPM_RH_OWNER),
key_handle,
StringFrom_TPM2B_NAME(key_name),
kSaltingKey,
owner_delegate.get());
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__ << ": " << GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPMT_PUBLIC TpmUtilityImpl::CreateDefaultPublicArea(TPM_ALG_ID key_alg) {
TPMT_PUBLIC public_area;
public_area.name_alg = TPM_ALG_SHA256;
public_area.auth_policy = Make_TPM2B_DIGEST("");
public_area.object_attributes = kFixedTPM | kFixedParent;
if (key_alg == TPM_ALG_RSA) {
public_area.type = TPM_ALG_RSA;
public_area.parameters.rsa_detail.scheme.scheme = TPM_ALG_NULL;
public_area.parameters.rsa_detail.symmetric.algorithm = TPM_ALG_NULL;
public_area.parameters.rsa_detail.key_bits = 2048;
public_area.parameters.rsa_detail.exponent = 0;
public_area.unique.rsa = Make_TPM2B_PUBLIC_KEY_RSA("");
} else if (key_alg == TPM_ALG_ECC) {
public_area.type = TPM_ALG_ECC;
public_area.parameters.ecc_detail.curve_id = TPM_ECC_NIST_P256;
public_area.parameters.ecc_detail.kdf.scheme = TPM_ALG_NULL;
public_area.unique.ecc.x = Make_TPM2B_ECC_PARAMETER("");
public_area.unique.ecc.y = Make_TPM2B_ECC_PARAMETER("");
} else if (key_alg == TPM_ALG_KEYEDHASH) {
public_area.type = TPM_ALG_KEYEDHASH;
public_area.parameters.keyed_hash_detail.scheme.scheme = TPM_ALG_NULL;
} else {
LOG(WARNING) << "Unrecognized key_type. Not filling parameters.";
}
return public_area;
}
TPM_RC TpmUtilityImpl::SetHierarchyAuthorization(
TPMI_RH_HIERARCHY_AUTH hierarchy,
const std::string& password,
AuthorizationDelegate* authorization) {
if (password.size() > kMaxPasswordLength) {
LOG(ERROR) << "Hierarchy passwords can be at most " << kMaxPasswordLength
<< " bytes. Current password length is: " << password.size();
return SAPI_RC_BAD_SIZE;
}
return factory_.GetTpm()->HierarchyChangeAuthSync(
hierarchy,
NameFromHandle(hierarchy),
Make_TPM2B_DIGEST(password),
authorization);
}
TPM_RC TpmUtilityImpl::DisablePlatformHierarchy(
AuthorizationDelegate* authorization) {
return factory_.GetTpm()->HierarchyControlSync(
TPM_RH_PLATFORM, // The authorizing entity.
NameFromHandle(TPM_RH_PLATFORM),
TPM_RH_PLATFORM, // The target hierarchy.
0, // Disable.
authorization);
}
TPM_RC TpmUtilityImpl::ComputeKeyName(const TPMT_PUBLIC& public_area,
std::string* object_name) {
CHECK(object_name);
if (public_area.type == TPM_ALG_ERROR) {
// We do not compute a name for empty public area.
object_name->clear();
return TPM_RC_SUCCESS;
}
std::string serialized_public_area;
TPM_RC result = Serialize_TPMT_PUBLIC(public_area, &serialized_public_area);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing public area: " << GetErrorString(result);
return result;
}
std::string serialized_name_alg;
result = Serialize_TPM_ALG_ID(TPM_ALG_SHA256, &serialized_name_alg);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing public area: " << GetErrorString(result);
return result;
}
object_name->assign(serialized_name_alg +
crypto::SHA256HashString(serialized_public_area));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::ComputeNVSpaceName(const TPMS_NV_PUBLIC& nv_public_area,
std::string* nv_name) {
CHECK(nv_name);
if ((nv_public_area.nv_index & NV_INDEX_FIRST) == 0) {
// If the index is not an nvram index, we do not compute a name.
nv_name->clear();
return TPM_RC_SUCCESS;
}
std::string serialized_public_area;
TPM_RC result = Serialize_TPMS_NV_PUBLIC(nv_public_area,
&serialized_public_area);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing public area: " << GetErrorString(result);
return result;
}
std::string serialized_name_alg;
result = Serialize_TPM_ALG_ID(TPM_ALG_SHA256, &serialized_name_alg);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing public area: " << GetErrorString(result);
return result;
}
nv_name->assign(serialized_name_alg +
crypto::SHA256HashString(serialized_public_area));
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::EncryptPrivateData(const TPMT_SENSITIVE& sensitive_area,
const TPMT_PUBLIC& public_area,
TPM2B_PRIVATE* encrypted_private_data,
TPM2B_DATA* encryption_key) {
TPM2B_SENSITIVE sensitive_data = Make_TPM2B_SENSITIVE(sensitive_area);
std::string serialized_sensitive_data;
TPM_RC result = Serialize_TPM2B_SENSITIVE(sensitive_data,
&serialized_sensitive_data);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing sensitive data: "
<< GetErrorString(result);
return result;
}
std::string object_name;
result = ComputeKeyName(public_area, &object_name);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error computing object name: " << GetErrorString(result);
return result;
}
TPM2B_DIGEST inner_integrity = Make_TPM2B_DIGEST(crypto::SHA256HashString(
serialized_sensitive_data + object_name));
std::string serialized_inner_integrity;
result = Serialize_TPM2B_DIGEST(inner_integrity, &serialized_inner_integrity);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error serializing inner integrity: "
<< GetErrorString(result);
return result;
}
std::string unencrypted_private_data = serialized_inner_integrity +
serialized_sensitive_data;
AES_KEY key;
AES_set_encrypt_key(encryption_key->buffer, kAesKeySize * 8, &key);
std::string private_data_string(unencrypted_private_data.size(), 0);
int iv_in = 0;
unsigned char iv[MAX_AES_BLOCK_SIZE_BYTES] = {0};
AES_cfb128_encrypt(
reinterpret_cast<const unsigned char*>(unencrypted_private_data.data()),
reinterpret_cast<unsigned char*>(string_as_array(&private_data_string)),
unencrypted_private_data.size(), &key, iv, &iv_in, AES_ENCRYPT);
*encrypted_private_data = Make_TPM2B_PRIVATE(private_data_string);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << "Error making private area: "
<< GetErrorString(result);
return result;
}
return TPM_RC_SUCCESS;
}
TPM_RC TpmUtilityImpl::DoesPersistentKeyExist(TPMI_DH_PERSISTENT key_handle,
bool* exists) {
TPM_RC result;
TPMI_YES_NO more_data = YES;
TPMS_CAPABILITY_DATA capability_data;
result = factory_.GetTpm()->GetCapabilitySync(
TPM_CAP_HANDLES, key_handle, 1 /*property_count*/, &more_data,
&capability_data, nullptr /*authorization_delegate*/);
if (result != TPM_RC_SUCCESS) {
LOG(ERROR) << __func__
<< ": Error querying handles: " << GetErrorString(result);
return result;
}
TPML_HANDLE& handles = capability_data.data.handles;
*exists = (handles.count == 1 && handles.handle[0] == key_handle);
return TPM_RC_SUCCESS;
}
} // namespace trunks