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Commit 40eb8f53 authored by David Drysdale's avatar David Drysdale
Browse files

KeyMint AIDL tweaks 

- Describe 3DES requirements
- Remove references to non-existent getKeyCharacteristics() entrypoint
- Remove references to non-existent attestKey() entrypoint
- Remove mention of asymmetric verification operations
- Remove text describing incomplete update()
- Remove text discussing padding for ECDSA
- EC keys can't encrypt/decrypt
- Force use of curve not key size for EC keys
- Drop TODO re: CBOR encoding of wrapped key
- Indicate caller-provided nonces must have correct size
- Add more reference to IKeyMintOperation
- Align parameter names with signatures
- Correct MIN_MAC_LENGTH error code
- Make CREATION_DATETIME consistently optional
- Describe use of MGF1 digest option
- Fix typos

Test: VtsKeyMintAidlTargetTest (CF)
Change-Id: Ie01b99d33be7336e872bf24a7761a3ac5b1d584c
parent b4be35f8

security/keymint/aidl/android/hardware/security/keymint/BeginResult.aidl

+4 −1
Original line number Diff line number Diff line
@@ -25,7 +25,10 @@ import android.hardware.security.keymint.KeyParameter; 
 */

@VintfStability

parcelable BeginResult {

    /* This is the challenge used in verifyAuthorization.  It must be a nonce. */

    /**

     * This is the challenge used to verify authorization of an operation.

     * See IKeyMintOperation.aidl entrypoints updateAad() and update().

     */

    long challenge;



    /**

security/keymint/aidl/android/hardware/security/keymint/IKeyMintDevice.aidl

+111 −95

File changed.

Preview size limit exceeded, changes collapsed.

security/keymint/aidl/android/hardware/security/keymint/IKeyMintOperation.aidl

+42 −66
Original line number Diff line number Diff line
@@ -31,12 +31,12 @@ interface IKeyMintOperation { 
     * update() is called.  If updateAad() is called after update(), it must return

     * ErrorCode::INVALID_TAG.

     *

     * If operation is in an invalid state (was aborted or had an error) update() must return

     * If the operation is in an invalid state (was aborted or had an error) update() must return

     * ErrorCode::INVALID_OPERATION_HANDLE.

     *

     * If this method returns an error code other than ErrorCode::OK, the operation is aborted and

     * the operation handle must be invalidated.  Any future use of the handle, with this method,

     * finish, or abort, must return ErrorCode::INVALID_OPERATION_HANDLE.

     * the operation handle must be invalidated.  Any future use of this object must return

     * ErrorCode::INVALID_OPERATION_HANDLE.

     *

     * == Authorization Enforcement ==

     *
@@ -58,9 +58,10 @@ interface IKeyMintOperation { 
     *

     *   o The key must have a Tag::USER_AUTH_TYPE that matches the auth type in the token.

     *

     *   o The challenge field in the auth token must contain the operationHandle

     *   o The challenge field in the auth token must contain the value returned from

     *     IKeyMintDevice::begin(), given by the challenge field of the BeginResult structure.

     *

     *   If any of these conditions are not met, update() must return

     *   If any of these conditions are not met, updateAad() must return

     *   ErrorCode::KEY_USER_NOT_AUTHENTICATED.

     *

     * The caller must provide the auth token on every call to updateAad(), update() and finish().
@@ -74,7 +75,7 @@ interface IKeyMintOperation { 
     *

     * @param input Additional Authentication Data to be processed.

     *

     * @param authToken Authentication token. Can be nullable if not provided.

     * @param authToken Authentication token, if provided.

     *

     * @param timeStampToken timestamp token, certifies the freshness of an auth token in case

     *        the security domain of this KeyMint instance has a different clock than the
@@ -93,18 +94,9 @@ interface IKeyMintOperation { 
     * If operation is in an invalid state (was aborted or had an error) update() must return

     * ErrorCode::INVALID_OPERATION_HANDLE.

     *

     * To provide more flexibility for buffer handling, implementations of this method have the

     * option of consuming less data than was provided.  The caller is responsible for looping to

     * feed the rest of the data in subsequent calls.  The amount of input consumed must be returned

     * in the inputConsumed parameter.  Implementations must always consume at least one byte,

     * unless the operation cannot accept any more; if more than zero bytes are provided and zero

     * bytes are consumed, callers must consider this an error and abort the operation.

     * TODO(seleneh) update the code to always consume alll the input data. b/168665179.

     *

     * Implementations may also choose how much data to return, as a result of the update.  This is

     * only relevant for encryption and decryption operations, because signing and verification

     * return no data until finish.  It is recommended to return data as early as possible, rather

     * than buffer it.

     * Implementations may choose how much data to return as a result of the update.  This is

     * only relevant for encryption and decryption operations, because signing returns no data

     * until finish.  It is recommended to return data as early as possible, rather than buffer it.

     *

     * If this method returns an error code other than ErrorCode::OK, the operation is aborted and

     * the operation handle must be invalidated.  Any future use of the handle, with this method,
@@ -112,8 +104,8 @@ interface IKeyMintOperation { 
     *

     * == Authorization Enforcement ==

     *

     * Key authorization enforcement is performed primarily in begin().  The one exception is the

     * case where the key has:

     * Key authorization enforcement is performed primarily in IKeyMintDevice::begin().  The one

     * exception is the case where the key has:

     *

     * o One or more Tag::USER_SECURE_IDs, and

     *
@@ -130,7 +122,8 @@ interface IKeyMintOperation { 
     *

     *   o The key must have a Tag::USER_AUTH_TYPE that matches the auth type in the token.

     *

     *   o The challenge field in the auth token must contain the operationHandle

     *   o The challenge field in the auth token must contain the challenge value contained in the

     *     BeginResult returned from IKeyMintDevice::begin().

     *

     *   If any of these conditions are not met, update() must return

     *   ErrorCode::KEY_USER_NOT_AUTHENTICATED.
@@ -139,22 +132,20 @@ interface IKeyMintOperation { 
     *

     * -- RSA keys --

     *

     * For signing and verification operations with Digest::NONE, this method must accept the entire

     * block to be signed or verified in a single update.  It may not consume only a portion of the

     * block in these cases.  However, the caller may choose to provide the data in multiple

     * updates, and update() must accept the data this way as well.  If the caller provides more

     * data to sign than can be used (length of data exceeds RSA key size), update() must return

     * ErrorCode::INVALID_INPUT_LENGTH.

     * For signing operations with Digest::NONE, this method must accept the entire block to be

     * signed in a single update.  It may not consume only a portion of the block in these cases.

     * However, the caller may choose to provide the data in multiple updates, and update() must

     * accept the data this way as well.  If the caller provides more data to sign than can be used

     * (length of data exceeds RSA key size), update() must return ErrorCode::INVALID_INPUT_LENGTH.

     *

     * -- ECDSA keys --

     *

     * For signing and verification operations with Digest::NONE, this method must accept the entire

     * block to be signed or verified in a single update.  This method may not consume only a

     * portion of the block.  However, the caller may choose to provide the data in multiple updates

     * and update() must accept the data this way as well.  If the caller provides more data to sign

     * than can be used, the data is silently truncated.  (This differs from the handling of excess

     * data provided in similar RSA operations.  The reason for this is compatibility with legacy

     * clients.)

     * For signing operations with Digest::NONE, this method must accept the entire block to be

     * signed in a single update.  This method may not consume only a portion of the block.

     * However, the caller may choose to provide the data in multiple updates and update() must

     * accept the data this way as well.  If the caller provides more data to sign than can be used,

     * the data is silently truncated.  (This differs from the handling of excess data provided in

     * similar RSA operations.  The reason for this is compatibility with legacy clients.)

     *

     * -- AES keys --

     *
@@ -182,7 +173,7 @@ interface IKeyMintOperation { 
            in @nullable TimeStampToken timeStampToken);



    /**

     * Finalizes a cryptographic operation begun with begin() and invalidates operation.

     * Finalizes a cryptographic operation begun with begin() and invalidates the operation.

     *

     * This method is the last one called in an operation, so all processed data must be returned.

     *
@@ -190,8 +181,7 @@ interface IKeyMintOperation { 
     * Any future use of the operation, with finish(), update(), or abort(), must return

     * ErrorCode::INVALID_OPERATION_HANDLE.

     *

     * Signing operations return the signature as the output.  Verification operations accept the

     * signature in the signature parameter, and return no output.

     * Signing operations return the signature as the output.

     *

     * == Authorization enforcement ==

     *
@@ -230,24 +220,19 @@ interface IKeyMintOperation { 
     * Some additional requirements, depending on the padding mode:

     *

     * o PaddingMode::NONE.  For unpadded signing and encryption operations, if the provided data is

     *   shorter than the key, the data must be zero-padded on the left before

     *   signing/encryption.  If the data is the same length as the key, but numerically larger,

     *   finish() must return ErrorCode::INVALID_ARGUMENT.  For verification and decryption

     *   operations, the data must be exactly as long as the key.  Otherwise, return

     *   ErrorCode::INVALID_INPUT_LENGTH.

     *   shorter than the key, the data must be zero-padded on the left before signing/encryption.

     *   If the data is the same length as the key, but numerically larger, finish() must return

     *   ErrorCode::INVALID_ARGUMENT.  For decryption operations, the data must be exactly as long

     *   as the key.  Otherwise, return ErrorCode::INVALID_INPUT_LENGTH.

     *

     * o PaddingMode::RSA_PSS.  For PSS-padded signature operations, the PSS salt length must match

     *   the size of the PSS digest selected.  The digest specified with Tag::DIGEST in inputParams

     *   the size of the PSS digest selected.  The digest specified with Tag::DIGEST in params

     *   on begin() must be used as the PSS digest algorithm, MGF1 must be used as the mask

     *   generation function and SHA1 must be used as the MGF1 digest algorithm.

     *

     * o PaddingMode::RSA_OAEP.  The digest specified with Tag::DIGEST in inputParams on begin is

     *   used as the OAEP digest algorithm, MGF1 must be used as the mask generation function and

     *   and SHA1 must be used as the MGF1 digest algorithm.

     *

     * -- ECDSA keys --

     *

     * If the data provided for unpadded signing or verification is too long, truncate it.

     * If the data provided for undigested signing is too long, truncate it.

     *

     * -- AES keys --

     *
@@ -256,18 +241,14 @@ interface IKeyMintOperation { 
     * o BlockMode::ECB or BlockMode::CBC.  If padding is PaddingMode::NONE and the data length is

     *   not a multiple of the AES block size, finish() must return

     *   ErrorCode::INVALID_INPUT_LENGTH.  If padding is PaddingMode::PKCS7, pad the data per the

     *  PKCS#7 specification, including adding an additional padding block if the data is a multiple

     *  of the block length.

     *   PKCS#7 specification, including adding an additional padding block if the data is a

     *   multiple of the block length.

     *

     * o BlockMode::GCM.  During encryption, after processing all plaintext, compute the tag

     *   (Tag::MAC_LENGTH bytes) and append it to the returned ciphertext.  During decryption,

     *   process the last Tag::MAC_LENGTH bytes as the tag.  If tag verification fails, finish()

     *   must return ErrorCode::VERIFICATION_FAILED.

     *

     * TODO: update() will need to be refactored into 2 function. b/168665179.

     *

     * @param inParams Additional parameters for the operation.

     *

     * @param input Data to be processed, per the parameters established in the call to begin().

     *        finish() must consume all provided data or return ErrorCode::INVALID_INPUT_LENGTH.

     *
@@ -284,8 +265,6 @@ interface IKeyMintOperation { 
     *        Tag::TRUSTED_CONFIRMATION_REQUIRED.

     *

     * @return The output data, if any.

     *

     * @return outParams Any output parameters generated by finish().

     */

    byte[] finish(in @nullable byte[] input, in @nullable byte[] signature,

            in @nullable HardwareAuthToken authToken,
@@ -293,13 +272,10 @@ interface IKeyMintOperation { 
            in @nullable byte[] confirmationToken);



    /**

     * Aborts a cryptographic operation begun with begin(), freeing all internal resources. If an

     * operation was finalized, calling update, finish, or abort yields

     * ErrorCode::INVALID_OPERATION_HANDLE. An operation is finalized if finish or abort was

     * called on it, or if update returned an ErrorCode.

     *

     * @param operationHandle The operation handle returned by begin().  This handle must be

     *        invalid when abort() returns.

     * Aborts a cryptographic operation begun with IKeyMintDevice::begin(), freeing all internal

     * resources.  If an operation was finalized, calling updateAad, update, finish, or abort yields

     * ErrorCode::INVALID_OPERATION_HANDLE. An operation is finalized if finish or abort was called

     * on it, or if updateAad or update returned an ErrorCode.

     *

     * @return error See the ErrorCode enum in ErrorCode.aidl.

     */

security/keymint/aidl/android/hardware/security/keymint/IRemotelyProvisionedComponent.aidl

+1 −1
Original line number Diff line number Diff line
@@ -78,7 +78,7 @@ import android.hardware.security.keymint.RpcHardwareInfo; 
 * While a proper BCC, as described above, reflects the complete boot sequence from boot ROM to the

 * secure area image of the IRemotelyProvisionedComponent, it's also possible to use a "degenerate"

 * BCC which consists only of a single, self-signed certificate containing the public key of a

 * hardware-bound key pair. This is an appopriate solution for devices which haven't implemented

 * hardware-bound key pair. This is an appropriate solution for devices which haven't implemented

 * everything necessary to produce a proper BCC, but can derive a unique key pair in the secure

 * area.  In this degenerate case, DK_pub is the same as KM_pub.

 *

security/keymint/aidl/android/hardware/security/keymint/KeyCreationResult.aidl

+2 −2
Original line number Diff line number Diff line
@@ -58,7 +58,7 @@ parcelable KeyCreationResult { 
     * There are a few variations in what is contained in `certificateChain`, depending on whether

     * the caller requested attestation, whether they provided an attestation key (via the

     * `attestationKey` parameter of `generateKey()`, `importKey()` or `importWrappedKey()`), and in

     * the non-attestaion case, whether the key can self-sign.

     * the non-attestation case, whether the key can self-sign.

     *

     * 1.  Asymmetric key attestation with factory key.  If Tag::ATTESTATION_CHALLENGE is provided

     *     and the `attestationKey` parameter on the generate/import call is null, the returned
@@ -70,7 +70,7 @@ parcelable KeyCreationResult { 
     *     attestation keys.

     *

     * 2.  Asymmetric key attestation with caller-provided key.  If Tag::ATTESTATION_CHALLENGE is

     *     provided and the `attestationKey` parameter on the generat/import call is non-null and

     *     provided and the `attestationKey` parameter on the generate/import call is non-null and

     *     contains the key blob of a key with KeyPurpose::ATTEST_KEY, the returned certificate

     *     chain must contain only an attestation certificate signed with the specified key.  The

     *     caller must know the certificate chain for the provided key.  Tag::