trusty_keymaster_context.h - trusty/app/keymaster - Git at Google

 /*
  * Copyright 2015 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.
  */

 #ifndef TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_
 #define TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_

 #include <stdlib.h>

 #include <keymaster/UniquePtr.h>
 #include <keymaster/attestation_context.h>
 #include <keymaster/keymaster_context.h>
 #include <keymaster/soft_key_factory.h>

 #include <keymaster/km_openssl/software_random_source.h>

 #include "trusty_keymaster_enforcement.h"
 #include "trusty_remote_provisioning_context.h"
 #include "trusty_secure_deletion_secret_storage.h"

 namespace keymaster {

 class KeyFactory;

 static const int kAuthTokenKeySize = 32;

 class TrustyKeymasterContext : public KeymasterContext,
                                AttestationContext,
                                SoftwareKeyBlobMaker,
                                SoftwareRandomSource {
 public:
     TrustyKeymasterContext();

     KmVersion GetKmVersion() const override {
         return AttestationContext::version_;
     }

     void SetKmVersion(KmVersion version) {
         AttestationContext::version_ = version;
     }

     keymaster_security_level_t GetSecurityLevel() const override {
         return KM_SECURITY_LEVEL_TRUSTED_ENVIRONMENT;
     }

     keymaster_error_t SetSystemVersion(uint32_t os_version,
                                        uint32_t os_patchlevel) override;
     void GetSystemVersion(uint32_t* os_version,
                           uint32_t* os_patchlevel) const override;

     const KeyFactory* GetKeyFactory(
             keymaster_algorithm_t algorithm) const override;
     OperationFactory* GetOperationFactory(
             keymaster_algorithm_t algorithm,
             keymaster_purpose_t purpose) const override;
     const keymaster_algorithm_t* GetSupportedAlgorithms(
             size_t* algorithms_count) const override;

     const VerifiedBootParams* GetVerifiedBootParams(
             keymaster_error_t* error) const override;

     keymaster_error_t CreateKeyBlob(
             const AuthorizationSet& key_description,
             keymaster_key_origin_t origin,
             const KeymasterKeyBlob& key_material,
             KeymasterKeyBlob* blob,
             AuthorizationSet* hw_enforced,
             AuthorizationSet* sw_enforced) const override;

     keymaster_error_t UpgradeKeyBlob(
             const KeymasterKeyBlob& key_to_upgrade,
             const AuthorizationSet& upgrade_params,
             KeymasterKeyBlob* upgraded_key) const override;

     keymaster_error_t ParseKeyBlob(const KeymasterKeyBlob& blob,
                                    const AuthorizationSet& additional_params,
                                    UniquePtr<Key>* key) const override;

     keymaster_error_t DeleteKey(const KeymasterKeyBlob& blob) const override;
     keymaster_error_t DeleteAllKeys() const override;

     keymaster_error_t AddRngEntropy(const uint8_t* buf,
                                     size_t length) const override;

     keymaster_error_t GetAuthTokenKey(keymaster_key_blob_t* key) const;

     KeymasterEnforcement* enforcement_policy() override {
         return &enforcement_policy_;
     }

     AttestationContext* attestation_context() override { return this; }

     SecureDeletionSecretStorage* secure_deletion_secret_storage() override {
         return &secure_deletion_secret_storage_;
     }

     keymaster_error_t VerifyAndCopyDeviceIds(
             const AuthorizationSet& attestation_params,
             AuthorizationSet* values_to_attest) const override;

     Buffer GenerateUniqueId(uint64_t creation_date_time,
                             const keymaster_blob_t& application_id,
                             bool reset_since_rotation,
                             keymaster_error_t* error) const override;

     KeymasterKeyBlob GetAttestationKey(keymaster_algorithm_t algorithm,
                                        keymaster_error_t* error) const override;

     CertificateChain GetAttestationChain(
             keymaster_algorithm_t algorithm,
             keymaster_error_t* error) const override;

     CertificateChain GenerateAttestation(
             const Key& key,
             const AuthorizationSet& attest_params,
             UniquePtr<Key> attest_key,
             const KeymasterBlob& issuer_subject,
             keymaster_error_t* error) const override;

     CertificateChain GenerateSelfSignedCertificate(
             const Key& key,
             const AuthorizationSet& cert_params,
             bool fake_signature,
             keymaster_error_t* error) const override;

     keymaster_error_t SetBootParams(
             uint32_t /* os_version */,
             uint32_t /* os_patchlevel */,
             const Buffer& verified_boot_key,
             keymaster_verified_boot_t verified_boot_state,
             bool device_locked,
             const Buffer& verified_boot_hash);

     virtual keymaster_error_t UnwrapKey(
             const KeymasterKeyBlob& wrapped_key_blob,
             const KeymasterKeyBlob& wrapping_key_blob,
             const AuthorizationSet& wrapping_key_params,
             const KeymasterKeyBlob& masking_key,
             AuthorizationSet* wrapped_key_params,
             keymaster_key_format_t* wrapped_key_format,
             KeymasterKeyBlob* wrapped_key_material) const override;

     keymaster_error_t CheckConfirmationToken(
             const uint8_t* input_data,
             size_t input_data_size,
             const uint8_t confirmation_token[kConfirmationTokenSize])
             const override;

     RemoteProvisioningContext* GetRemoteProvisioningContext() const override {
         return trusty_remote_provisioning_context_.get();
     }

     keymaster_error_t SetVendorPatchlevel(uint32_t vendor_patchlevel) override {
         if (vendor_patchlevel_.has_value() &&
             vendor_patchlevel != vendor_patchlevel_.value()) {
             // Can't set patchlevel to a different value.
             return KM_ERROR_INVALID_ARGUMENT;
         }
         vendor_patchlevel_ = vendor_patchlevel;
         trusty_remote_provisioning_context_->SetVendorPatchlevel(
                 vendor_patchlevel);
         return KM_ERROR_OK;
     }

     keymaster_error_t SetBootPatchlevel(uint32_t boot_patchlevel) override {
         if (boot_patchlevel_.has_value() &&
             boot_patchlevel != boot_patchlevel_.value()) {
             // Can't set patchlevel to a different value.
             return KM_ERROR_INVALID_ARGUMENT;
         }
         boot_patchlevel_ = boot_patchlevel;
         trusty_remote_provisioning_context_->SetBootPatchlevel(boot_patchlevel);
         return KM_ERROR_OK;
     }

     std::optional<uint32_t> GetVendorPatchlevel() const override {
         return vendor_patchlevel_;
     }

     std::optional<uint32_t> GetBootPatchlevel() const override {
         return boot_patchlevel_;
     }

 private:
     bool SeedRngIfNeeded() const;
     bool ShouldReseedRng() const;
     bool ReseedRng();
     bool InitializeAuthTokenKey();
     keymaster_error_t SetAuthorizations(const AuthorizationSet& key_description,
                                         keymaster_key_origin_t origin,
                                         AuthorizationSet* hw_enforced,
                                         AuthorizationSet* sw_enforced,
                                         bool has_secure_deletion) const;
     keymaster_error_t BuildHiddenAuthorizations(
             const AuthorizationSet& input_set,
             AuthorizationSet* hidden) const;
     keymaster_error_t DeriveMasterKey(KeymasterKeyBlob* master_key,
                                       const EncryptedKey& enc_key) const;
     keymaster_error_t GetKdfState(EncryptedKey* info) const;
     KmErrorOr<DeserializedKey> DeserializeKmCompatKeyBlob(
             const KeymasterKeyBlob& blob) const;
     KmErrorOr<DeserializedKey> DeserializeKeyBlob(
             const KeymasterKeyBlob& blob) const;

     /*
      * CreateAuthEncryptedKeyBlob takes a key description authorization set, key
      * material, and hardware and software authorization sets and produces an
      * encrypted and integrity-checked key blob.
      *
      * This method is called by CreateKeyBlob and UpgradeKeyBlob.
      */
     keymaster_error_t CreateAuthEncryptedKeyBlob(
             const AuthorizationSet& key_description,
             const KeymasterKeyBlob& key_material,
             const AuthorizationSet& hw_enforced,
             const AuthorizationSet& sw_enforced,
             const std::optional<SecureDeletionData>& secure_deletion_data,
             KeymasterKeyBlob* blob) const;

     TrustyKeymasterEnforcement enforcement_policy_;
     TrustySecureDeletionSecretStorage secure_deletion_secret_storage_;

     UniquePtr<KeyFactory> aes_factory_;
     UniquePtr<KeyFactory> ec_factory_;
     UniquePtr<KeyFactory> hmac_factory_;
     UniquePtr<KeyFactory> rsa_factory_;
     UniquePtr<KeyFactory> tdes_factory_;

     bool rng_initialized_;
     mutable int calls_since_reseed_;
     uint8_t auth_token_key_[kAuthTokenKeySize];
     bool auth_token_key_initialized_;

     bool root_of_trust_set_ = false;
     bool version_info_set_ = false;
     BootParams boot_params_;
     VerifiedBootParams verified_boot_params_ = {
             .verified_boot_key = {},
             .verified_boot_hash = {},
             .verified_boot_state = KM_VERIFIED_BOOT_UNVERIFIED,
             .device_locked = false};
     UniquePtr<TrustyRemoteProvisioningContext>
             trusty_remote_provisioning_context_;
     std::optional<uint32_t> vendor_patchlevel_;
     std::optional<uint32_t> boot_patchlevel_;
     mutable std::vector<uint8_t> unique_id_hbk_;
 };

 }  // namespace keymaster

 #endif  // TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_
	/*
	* Copyright 2015 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.
	*/

	#ifndef TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_
	#define TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_

	#include <stdlib.h>

	#include <keymaster/UniquePtr.h>
	#include <keymaster/attestation_context.h>
	#include <keymaster/keymaster_context.h>
	#include <keymaster/soft_key_factory.h>

	#include <keymaster/km_openssl/software_random_source.h>

	#include "trusty_keymaster_enforcement.h"
	#include "trusty_remote_provisioning_context.h"
	#include "trusty_secure_deletion_secret_storage.h"

	namespace keymaster {

	class KeyFactory;

	static const int kAuthTokenKeySize = 32;

	class TrustyKeymasterContext : public KeymasterContext,
	AttestationContext,
	SoftwareKeyBlobMaker,
	SoftwareRandomSource {
	public:
	TrustyKeymasterContext();

	KmVersion GetKmVersion() const override {
	return AttestationContext::version_;
	}

	void SetKmVersion(KmVersion version) {
	AttestationContext::version_ = version;
	}

	keymaster_security_level_t GetSecurityLevel() const override {
	return KM_SECURITY_LEVEL_TRUSTED_ENVIRONMENT;
	}

	keymaster_error_t SetSystemVersion(uint32_t os_version,
	uint32_t os_patchlevel) override;
	void GetSystemVersion(uint32_t* os_version,
	uint32_t* os_patchlevel) const override;

	const KeyFactory* GetKeyFactory(
	keymaster_algorithm_t algorithm) const override;
	OperationFactory* GetOperationFactory(
	keymaster_algorithm_t algorithm,
	keymaster_purpose_t purpose) const override;
	const keymaster_algorithm_t* GetSupportedAlgorithms(
	size_t* algorithms_count) const override;

	const VerifiedBootParams* GetVerifiedBootParams(
	keymaster_error_t* error) const override;

	keymaster_error_t CreateKeyBlob(
	const AuthorizationSet& key_description,
	keymaster_key_origin_t origin,
	const KeymasterKeyBlob& key_material,
	KeymasterKeyBlob* blob,
	AuthorizationSet* hw_enforced,
	AuthorizationSet* sw_enforced) const override;

	keymaster_error_t UpgradeKeyBlob(
	const KeymasterKeyBlob& key_to_upgrade,
	const AuthorizationSet& upgrade_params,
	KeymasterKeyBlob* upgraded_key) const override;

	keymaster_error_t ParseKeyBlob(const KeymasterKeyBlob& blob,
	const AuthorizationSet& additional_params,
	UniquePtr<Key>* key) const override;

	keymaster_error_t DeleteKey(const KeymasterKeyBlob& blob) const override;
	keymaster_error_t DeleteAllKeys() const override;

	keymaster_error_t AddRngEntropy(const uint8_t* buf,
	size_t length) const override;

	keymaster_error_t GetAuthTokenKey(keymaster_key_blob_t* key) const;

	KeymasterEnforcement* enforcement_policy() override {
	return &enforcement_policy_;
	}

	AttestationContext* attestation_context() override { return this; }

	SecureDeletionSecretStorage* secure_deletion_secret_storage() override {
	return &secure_deletion_secret_storage_;
	}

	keymaster_error_t VerifyAndCopyDeviceIds(
	const AuthorizationSet& attestation_params,
	AuthorizationSet* values_to_attest) const override;

	Buffer GenerateUniqueId(uint64_t creation_date_time,
	const keymaster_blob_t& application_id,
	bool reset_since_rotation,
	keymaster_error_t* error) const override;

	KeymasterKeyBlob GetAttestationKey(keymaster_algorithm_t algorithm,
	keymaster_error_t* error) const override;

	CertificateChain GetAttestationChain(
	keymaster_algorithm_t algorithm,
	keymaster_error_t* error) const override;

	CertificateChain GenerateAttestation(
	const Key& key,
	const AuthorizationSet& attest_params,
	UniquePtr<Key> attest_key,
	const KeymasterBlob& issuer_subject,
	keymaster_error_t* error) const override;

	CertificateChain GenerateSelfSignedCertificate(
	const Key& key,
	const AuthorizationSet& cert_params,
	bool fake_signature,
	keymaster_error_t* error) const override;

	keymaster_error_t SetBootParams(
	uint32_t /* os_version */,
	uint32_t /* os_patchlevel */,
	const Buffer& verified_boot_key,
	keymaster_verified_boot_t verified_boot_state,
	bool device_locked,
	const Buffer& verified_boot_hash);

	virtual keymaster_error_t UnwrapKey(
	const KeymasterKeyBlob& wrapped_key_blob,
	const KeymasterKeyBlob& wrapping_key_blob,
	const AuthorizationSet& wrapping_key_params,
	const KeymasterKeyBlob& masking_key,
	AuthorizationSet* wrapped_key_params,
	keymaster_key_format_t* wrapped_key_format,
	KeymasterKeyBlob* wrapped_key_material) const override;

	keymaster_error_t CheckConfirmationToken(
	const uint8_t* input_data,
	size_t input_data_size,
	const uint8_t confirmation_token[kConfirmationTokenSize])
	const override;

	RemoteProvisioningContext* GetRemoteProvisioningContext() const override {
	return trusty_remote_provisioning_context_.get();
	}

	keymaster_error_t SetVendorPatchlevel(uint32_t vendor_patchlevel) override {
	if (vendor_patchlevel_.has_value() &&
	vendor_patchlevel != vendor_patchlevel_.value()) {
	// Can't set patchlevel to a different value.
	return KM_ERROR_INVALID_ARGUMENT;
	}
	vendor_patchlevel_ = vendor_patchlevel;
	trusty_remote_provisioning_context_->SetVendorPatchlevel(
	vendor_patchlevel);
	return KM_ERROR_OK;
	}

	keymaster_error_t SetBootPatchlevel(uint32_t boot_patchlevel) override {
	if (boot_patchlevel_.has_value() &&
	boot_patchlevel != boot_patchlevel_.value()) {
	// Can't set patchlevel to a different value.
	return KM_ERROR_INVALID_ARGUMENT;
	}
	boot_patchlevel_ = boot_patchlevel;
	trusty_remote_provisioning_context_->SetBootPatchlevel(boot_patchlevel);
	return KM_ERROR_OK;
	}

	std::optional<uint32_t> GetVendorPatchlevel() const override {
	return vendor_patchlevel_;
	}

	std::optional<uint32_t> GetBootPatchlevel() const override {
	return boot_patchlevel_;
	}

	private:
	bool SeedRngIfNeeded() const;
	bool ShouldReseedRng() const;
	bool ReseedRng();
	bool InitializeAuthTokenKey();
	keymaster_error_t SetAuthorizations(const AuthorizationSet& key_description,
	keymaster_key_origin_t origin,
	AuthorizationSet* hw_enforced,
	AuthorizationSet* sw_enforced,
	bool has_secure_deletion) const;
	keymaster_error_t BuildHiddenAuthorizations(
	const AuthorizationSet& input_set,
	AuthorizationSet* hidden) const;
	keymaster_error_t DeriveMasterKey(KeymasterKeyBlob* master_key,
	const EncryptedKey& enc_key) const;
	keymaster_error_t GetKdfState(EncryptedKey* info) const;
	KmErrorOr<DeserializedKey> DeserializeKmCompatKeyBlob(
	const KeymasterKeyBlob& blob) const;
	KmErrorOr<DeserializedKey> DeserializeKeyBlob(
	const KeymasterKeyBlob& blob) const;

	/*
	* CreateAuthEncryptedKeyBlob takes a key description authorization set, key
	* material, and hardware and software authorization sets and produces an
	* encrypted and integrity-checked key blob.
	*
	* This method is called by CreateKeyBlob and UpgradeKeyBlob.
	*/
	keymaster_error_t CreateAuthEncryptedKeyBlob(
	const AuthorizationSet& key_description,
	const KeymasterKeyBlob& key_material,
	const AuthorizationSet& hw_enforced,
	const AuthorizationSet& sw_enforced,
	const std::optional<SecureDeletionData>& secure_deletion_data,
	KeymasterKeyBlob* blob) const;

	TrustyKeymasterEnforcement enforcement_policy_;
	TrustySecureDeletionSecretStorage secure_deletion_secret_storage_;

	UniquePtr<KeyFactory> aes_factory_;
	UniquePtr<KeyFactory> ec_factory_;
	UniquePtr<KeyFactory> hmac_factory_;
	UniquePtr<KeyFactory> rsa_factory_;
	UniquePtr<KeyFactory> tdes_factory_;

	bool rng_initialized_;
	mutable int calls_since_reseed_;
	uint8_t auth_token_key_[kAuthTokenKeySize];
	bool auth_token_key_initialized_;

	bool root_of_trust_set_ = false;
	bool version_info_set_ = false;
	BootParams boot_params_;
	VerifiedBootParams verified_boot_params_ = {
	.verified_boot_key = {},
	.verified_boot_hash = {},
	.verified_boot_state = KM_VERIFIED_BOOT_UNVERIFIED,
	.device_locked = false};
	UniquePtr<TrustyRemoteProvisioningContext>
	trusty_remote_provisioning_context_;
	std::optional<uint32_t> vendor_patchlevel_;
	std::optional<uint32_t> boot_patchlevel_;
	mutable std::vector<uint8_t> unique_id_hbk_;
	};

	} // namespace keymaster

	#endif // TRUSTY_APP_KEYMASTER_TRUSTY_KEYMASTER_CONTEXT_H_