Merge "KeyMint: Fix device-unique attestation chain specification" (9c3bd29c) · Commits · e / os / android_hardware_interfaces

security/keymint/aidl/android/hardware/security/keymint/Tag.aidl

+14 −3

Original line number	Diff line number	Diff line
		@@ -827,11 +827,22 @@ enum Tag {
		/**
		* DEVICE_UNIQUE_ATTESTATION is an argument to IKeyMintDevice::attested key generation/import
		* operations. It indicates that attestation using a device-unique key is requested, rather
		* than a batch key. When a device-unique key is used, the returned chain should contain two
		* certificates:
		* than a batch key. When a device-unique key is used, the returned chain should contain two or
		* three certificates.
		*
		* In case the chain contains two certificates, they should be:
		* * The attestation certificate, containing the attestation extension, as described in
		KeyCreationResult.aidl.
		* KeyCreationResult.aidl.
		* * A self-signed root certificate, signed by the device-unique key.
		*
		* In case the chain contains three certificates, they should be:
		* * The attestation certificate, containing the attestation extension, as described in
		* KeyCreationResult.aidl, signed by the device-unique key.
		* * An intermediate certificate, containing the public portion of the device-unique key.
		* * A self-signed root certificate, signed by a dedicated key, certifying the
		* intermediate. Ideally, the dedicated key would be the same for all StrongBox
		* instances of the same manufacturer to ease validation.
		*
		* No additional chained certificates are provided. Only SecurityLevel::STRONGBOX
		* IKeyMintDevices may support device-unique attestations. SecurityLevel::TRUSTED_ENVIRONMENT
		* IKeyMintDevices must return ErrorCode::INVALID_ARGUMENT if they receive

security/keymint/aidl/vts/functional/DeviceUniqueAttestationTest.cpp

+9 −4

Original line number	Diff line number	Diff line
		@@ -40,11 +40,16 @@ class DeviceUniqueAttestationTest : public KeyMintAidlTestBase {

		AuthorizationSet crypto_params = SecLevelAuthorizations(key_characteristics);

		// The device-unique attestation chain should contain exactly two certificates:
		// The device-unique attestation chain should contain exactly three certificates:
		// * The leaf with the attestation extension.
		// * A self-signed root, signed using the device-unique key.
		ASSERT_EQ(cert_chain_.size(), 2);
		EXPECT_TRUE(ChainSignaturesAreValid(cert_chain_));
		// * An intermediate, signing the leaf using the device-unique key.
		// * A self-signed root, signed using some authority's key, certifying
		// the device-unique key.
		const size_t chain_length = cert_chain_.size();
		ASSERT_TRUE(chain_length == 2 \|\| chain_length == 3);
		// TODO(b/191361618): Once StrongBox implementations use a correctly-issued
		// certificate chain, do not skip issuers matching.
		EXPECT_TRUE(ChainSignaturesAreValid(cert_chain_, /* strict_issuer_check= */ false));

		AuthorizationSet sw_enforced = SwEnforcedAuthorizations(key_characteristics);
		EXPECT_TRUE(verify_attestation_record("challenge", "foo", sw_enforced, hw_enforced,

security/keymint/aidl/vts/functional/KeyMintAidlTestBase.cpp

+3 −2

Original line number	Diff line number	Diff line
		@@ -1493,7 +1493,8 @@ AuthorizationSet SwEnforcedAuthorizations(const vector<KeyCharacteristics>& key_
		return authList;
		}

		AssertionResult ChainSignaturesAreValid(const vector<Certificate>& chain) {
		AssertionResult ChainSignaturesAreValid(const vector<Certificate>& chain,
		bool strict_issuer_check) {
		std::stringstream cert_data;

		for (size_t i = 0; i < chain.size(); ++i) {
		@@ -1520,7 +1521,7 @@ AssertionResult ChainSignaturesAreValid(const vector<Certificate>& chain) {

		string cert_issuer = x509NameToStr(X509_get_issuer_name(key_cert.get()));
		string signer_subj = x509NameToStr(X509_get_subject_name(signing_cert.get()));
		if (cert_issuer != signer_subj) {
		if (cert_issuer != signer_subj && strict_issuer_check) {
		return AssertionFailure() << "Cert " << i << " has wrong issuer.\n"
		<< " Signer subject is " << signer_subj
		<< " Issuer subject is " << cert_issuer << endl

security/keymint/aidl/vts/functional/KeyMintAidlTestBase.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -349,7 +349,8 @@ void p256_pub_key(const vector<uint8_t>& coseKeyData, EVP_PKEY_Ptr* signingKey);

		AuthorizationSet HwEnforcedAuthorizations(const vector<KeyCharacteristics>& key_characteristics);
		AuthorizationSet SwEnforcedAuthorizations(const vector<KeyCharacteristics>& key_characteristics);
		::testing::AssertionResult ChainSignaturesAreValid(const vector<Certificate>& chain);
		::testing::AssertionResult ChainSignaturesAreValid(const vector<Certificate>& chain,
		bool strict_issuer_check = true);

		#define INSTANTIATE_KEYMINT_AIDL_TEST(name) \
		INSTANTIATE_TEST_SUITE_P(PerInstance, name, \