am ada70be8: Merge "Add KM_MIN_MAC_LENGTH tag to HMAC and AES-GCM keys." into mnc-dev (568e67a3) · Commits · e / os / android_frameworks_base

core/java/android/security/keymaster/KeymasterDefs.java

+6 −0

Original line number	Diff line number	Diff line
		@@ -51,6 +51,7 @@ public final class KeymasterDefs {
		public static final int KM_TAG_DIGEST = KM_ENUM_REP \| 5;
		public static final int KM_TAG_PADDING = KM_ENUM_REP \| 6;
		public static final int KM_TAG_CALLER_NONCE = KM_BOOL \| 7;
		public static final int KM_TAG_MIN_MAC_LENGTH = KM_UINT \| 8;

		public static final int KM_TAG_RESCOPING_ADD = KM_ENUM_REP \| 101;
		public static final int KM_TAG_RESCOPING_DEL = KM_ENUM_REP \| 102;
		@@ -194,6 +195,9 @@ public final class KeymasterDefs {
		public static final int KM_ERROR_KEY_RATE_LIMIT_EXCEEDED = -54;
		public static final int KM_ERROR_CALLER_NONCE_PROHIBITED = -55;
		public static final int KM_ERROR_KEY_MAX_OPS_EXCEEDED = -56;
		public static final int KM_ERROR_INVALID_MAC_LENGTH = -57;
		public static final int KM_ERROR_MISSING_MIN_MAC_LENGTH = -58;
		public static final int KM_ERROR_UNSUPPORTED_MIN_MAC_LENGTH = -59;
		public static final int KM_ERROR_UNIMPLEMENTED = -100;
		public static final int KM_ERROR_VERSION_MISMATCH = -101;
		public static final int KM_ERROR_UNKNOWN_ERROR = -1000;
		@@ -237,6 +241,8 @@ public final class KeymasterDefs {
		sErrorCodeToString.put(KM_ERROR_INVALID_NONCE, "Invalid IV");
		sErrorCodeToString.put(KM_ERROR_CALLER_NONCE_PROHIBITED,
		"Caller-provided IV not permitted");
		sErrorCodeToString.put(KM_ERROR_INVALID_MAC_LENGTH,
		"Invalid MAC or authentication tag length");
		sErrorCodeToString.put(KM_ERROR_UNIMPLEMENTED, "Not implemented");
		sErrorCodeToString.put(KM_ERROR_UNKNOWN_ERROR, "Unknown error");
		}

keystore/java/android/security/keystore/AndroidKeyStoreAuthenticatedAESCipherSpi.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -51,7 +51,7 @@ import javax.crypto.spec.GCMParameterSpec;
		abstract class AndroidKeyStoreAuthenticatedAESCipherSpi extends AndroidKeyStoreCipherSpiBase {

		abstract static class GCM extends AndroidKeyStoreAuthenticatedAESCipherSpi {
		private static final int MIN_SUPPORTED_TAG_LENGTH_BITS = 96;
		static final int MIN_SUPPORTED_TAG_LENGTH_BITS = 96;
		private static final int MAX_SUPPORTED_TAG_LENGTH_BITS = 128;
		private static final int DEFAULT_TAG_LENGTH_BITS = 128;
		private static final int IV_LENGTH_BYTES = 12;

keystore/java/android/security/keystore/AndroidKeyStoreKeyGeneratorSpi.java

+6 −1

Original line number	Diff line number	Diff line
		@@ -171,7 +171,7 @@ public abstract class AndroidKeyStoreKeyGeneratorSpi extends KeyGeneratorSpi {
		"Key size must be positive: " + mKeySizeBits);
		} else if ((mKeySizeBits % 8) != 0) {
		throw new InvalidAlgorithmParameterException(
		"Key size in must be a multiple of 8: " + mKeySizeBits);
		"Key size must be a multiple of 8: " + mKeySizeBits);
		}

		try {
		@@ -272,6 +272,11 @@ public abstract class AndroidKeyStoreKeyGeneratorSpi extends KeyGeneratorSpi {
		KeymasterUtils.addUserAuthArgs(args,
		spec.isUserAuthenticationRequired(),
		spec.getUserAuthenticationValidityDurationSeconds());
		KeymasterUtils.addMinMacLengthAuthorizationIfNecessary(
		args,
		mKeymasterAlgorithm,
		mKeymasterBlockModes,
		mKeymasterDigests);
		args.addDateIfNotNull(KeymasterDefs.KM_TAG_ACTIVE_DATETIME, spec.getKeyValidityStart());
		args.addDateIfNotNull(KeymasterDefs.KM_TAG_ORIGINATION_EXPIRE_DATETIME,
		spec.getKeyValidityForOriginationEnd());

keystore/java/android/security/keystore/AndroidKeyStoreSpi.java

+5 −0

Original line number	Diff line number	Diff line
		@@ -672,6 +672,11 @@ public class AndroidKeyStoreSpi extends KeyStoreSpi {
		KeymasterUtils.addUserAuthArgs(args,
		params.isUserAuthenticationRequired(),
		params.getUserAuthenticationValidityDurationSeconds());
		KeymasterUtils.addMinMacLengthAuthorizationIfNecessary(
		args,
		keymasterAlgorithm,
		keymasterBlockModes,
		keymasterDigests);
		args.addDateIfNotNull(KeymasterDefs.KM_TAG_ACTIVE_DATETIME,
		params.getKeyValidityStart());
		args.addDateIfNotNull(KeymasterDefs.KM_TAG_ORIGINATION_EXPIRE_DATETIME,

keystore/java/android/security/keystore/KeymasterUtils.java

+43 −0

Original line number	Diff line number	Diff line
		@@ -22,6 +22,8 @@ import android.security.KeyStore;
		import android.security.keymaster.KeymasterArguments;
		import android.security.keymaster.KeymasterDefs;

		import java.security.ProviderException;

		/**
		* @hide
		*/
		@@ -133,4 +135,45 @@ public abstract class KeymasterUtils {
		userAuthenticationValidityDurationSeconds);
		}
		}

		/**
		* Adds {@code KM_TAG_MIN_MAC_LENGTH} tag, if necessary, to the keymaster arguments for
		* generating or importing a key. This tag may only be needed for symmetric keys (e.g., HMAC,
		* AES-GCM).
		*/
		public static void addMinMacLengthAuthorizationIfNecessary(KeymasterArguments args,
		int keymasterAlgorithm,
		int[] keymasterBlockModes,
		int[] keymasterDigests) {
		switch (keymasterAlgorithm) {
		case KeymasterDefs.KM_ALGORITHM_AES:
		if (com.android.internal.util.ArrayUtils.contains(
		keymasterBlockModes, KeymasterDefs.KM_MODE_GCM)) {
		// AES GCM key needs the minimum length of AEAD tag specified.
		args.addUnsignedInt(KeymasterDefs.KM_TAG_MIN_MAC_LENGTH,
		AndroidKeyStoreAuthenticatedAESCipherSpi.GCM
		.MIN_SUPPORTED_TAG_LENGTH_BITS);
		}
		break;
		case KeymasterDefs.KM_ALGORITHM_HMAC:
		// HMAC key needs the minimum length of MAC set to the output size of the associated
		// digest. This is because we do not offer a way to generate shorter MACs and
		// don't offer a way to verify MACs (other than by generating them).
		if (keymasterDigests.length != 1) {
		throw new ProviderException(
		"Unsupported number of authorized digests for HMAC key: "
		+ keymasterDigests.length
		+ ". Exactly one digest must be authorized");
		}
		int keymasterDigest = keymasterDigests[0];
		int digestOutputSizeBits = getDigestOutputSizeBits(keymasterDigest);
		if (digestOutputSizeBits == -1) {
		throw new ProviderException(
		"HMAC key authorized for unsupported digest: "
		+ KeyProperties.Digest.fromKeymaster(keymasterDigest));
		}
		args.addUnsignedInt(KeymasterDefs.KM_TAG_MIN_MAC_LENGTH, digestOutputSizeBits);
		break;
		}
		}
		}