decrypt ¶

def decrypt(
    self,
    *,
    config_overrides: Optional[KMSClientConfig] = None,
    ciphertext_blob: Optional[
        "capo_kms.types.ciphertext_type.CiphertextType"
    ] = None,
    encryption_context: Optional[
        "capo_kms.types.encryption_context_type.EncryptionContextType"
    ] = None,
    grant_tokens: Optional["capo_kms.types.grant_token_list.GrantTokenList"] = None,
    key_id: Optional["capo_kms.types.key_id_type.KeyIdType"] = None,
    encryption_algorithm: Optional[
        "capo_kms.types.encryption_algorithm_spec.EncryptionAlgorithmSpec"
    ] = None,
    recipient: Optional["capo_kms.types.recipient_info.RecipientInfo"] = None,
    dry_run: Optional[
        "capo_kms.types.nullable_boolean_type.NullableBooleanType"
    ] = None,
    dry_run_modifiers: Optional[
        "capo_kms.types.dry_run_modifier_list.DryRunModifierList"
    ] = None,
) -> "capo_kms.types.decrypt_response.DecryptResponse":
    """<p>Decrypts ciphertext that was encrypted by a KMS key using any of the following operations:</p> <ul> <li> <p> <a>Encrypt</a> </p> </li> <li> <p> <a>GenerateDataKey</a> </p> </li> <li> <p> <a>GenerateDataKeyPair</a> </p> </li> <li> <p> <a>GenerateDataKeyWithoutPlaintext</a> </p> </li> <li> <p> <a>GenerateDataKeyPairWithoutPlaintext</a> </p> </li> </ul> <p>You can use this operation to decrypt ciphertext that was encrypted under a symmetric encryption KMS key or an asymmetric encryption KMS key. When the KMS key is asymmetric, you must specify the KMS key and the encryption algorithm that was used to encrypt the ciphertext. For information about asymmetric KMS keys, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/symmetric-asymmetric.html">Asymmetric KMS keys</a> in the <i>Key Management Service Developer Guide</i>.</p> <p>The <code>Decrypt</code> operation also decrypts ciphertext that was encrypted outside of KMS by the public key in an KMS asymmetric KMS key. However, it cannot decrypt symmetric ciphertext produced by other libraries, such as the <a href="https://docs.aws.amazon.com/encryption-sdk/latest/developer-guide/">Amazon Web Services Encryption SDK</a> or <a href="https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingClientSideEncryption.html">Amazon S3 client-side encryption</a>. These libraries return a ciphertext format that is incompatible with KMS.</p> <p>If the ciphertext was encrypted under a symmetric encryption KMS key, the <code>KeyId</code> parameter is optional. KMS can get this information from metadata that it adds to the symmetric ciphertext blob. This feature adds durability to your implementation by ensuring that authorized users can decrypt ciphertext decades after it was encrypted, even if they've lost track of the key ID. However, specifying the KMS key is always recommended as a best practice. When you use the <code>KeyId</code> parameter to specify a KMS key, KMS only uses the KMS key you specify. If the ciphertext was encrypted under a different KMS key, the <code>Decrypt</code> operation fails. This practice ensures that you use the KMS key that you intend.</p> <p>Whenever possible, use key policies to give users permission to call the <code>Decrypt</code> operation on a particular KMS key, instead of using IAM policies. Otherwise, you might create an IAM policy that gives the user <code>Decrypt</code> permission on all KMS keys. This user could decrypt ciphertext that was encrypted by KMS keys in other accounts if the key policy for the cross-account KMS key permits it. If you must use an IAM policy for <code>Decrypt</code> permissions, limit the user to particular KMS keys or particular trusted accounts. For details, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/iam-policies.html#iam-policies-best-practices">Best practices for IAM policies</a> in the <i>Key Management Service Developer Guide</i>.</p> <p> <code>Decrypt</code> also supports <a href="https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/nitro-enclave.html">Amazon Web Services Nitro Enclaves</a> and NitroTPM, which provide attested environments in Amazon EC2. To call <code>Decrypt</code> for a Nitro enclave or NitroTPM, use the <a href="https://docs.aws.amazon.com/enclaves/latest/user/developing-applications.html#sdk">Amazon Web Services Nitro Enclaves SDK</a> or any Amazon Web Services SDK. Use the <code>Recipient</code> parameter to provide the attestation document for the attested environment. Instead of the plaintext data, the response includes the plaintext data encrypted with the public key from the attestation document (<code>CiphertextForRecipient</code>). For information about the interaction between KMS and Amazon Web Services Nitro Enclaves or Amazon Web Services NitroTPM, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/cryptographic-attestation.html">Cryptographic attestation support in KMS</a> in the <i>Key Management Service Developer Guide</i>.</p> <p>The KMS key that you use for this operation must be in a compatible key state. For details, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/key-state.html">Key states of KMS keys</a> in the <i>Key Management Service Developer Guide</i>.</p> <p> <b>Cross-account use</b>: Yes. To specify a KMS key in a different Amazon Web Services account, use the <a href="https://docs.aws.amazon.com/kms/latest/developerguide/concepts.html#key-id-key-ARN">key ARN</a> or <a href="https://docs.aws.amazon.com/kms/latest/developerguide/concepts.html#key-id-alias-ARN">alias ARN</a>. A short <a href="https://docs.aws.amazon.com/kms/latest/developerguide/concepts.html#key-id-key-id">key ID</a> is also acceptable when decrypting symmetric ciphertexts, though using a full key ARN is recommended to be more explicit about the intended KMS key.</p> <p> <b>Required permissions</b>: <a href="https://docs.aws.amazon.com/kms/latest/developerguide/kms-api-permissions-reference.html">kms:Decrypt</a> (key policy)</p> <p> <b>Related operations:</b> </p> <ul> <li> <p> <a>Encrypt</a> </p> </li> <li> <p> <a>GenerateDataKey</a> </p> </li> <li> <p> <a>GenerateDataKeyPair</a> </p> </li> <li> <p> <a>ReEncrypt</a> </p> </li> </ul> <p> <b>Eventual consistency</b>: The KMS API follows an eventual consistency model. For more information, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/accessing-kms.html#programming-eventual-consistency">KMS eventual consistency</a>.</p>

    Args:
        ciphertext_blob: <p>Ciphertext to be decrypted. The blob includes metadata.</p> <p>This parameter is required in all cases except when <code>DryRun</code> is <code>true</code> and <code>DryRunModifiers</code> is set to <code>IGNORE_CIPHERTEXT</code>.</p>
        encryption_context: <p>Specifies the encryption context to use when decrypting the data. An encryption context is valid only for <a href="https://docs.aws.amazon.com/kms/latest/developerguide/kms-cryptography.html#cryptographic-operations">cryptographic operations</a> with a symmetric encryption KMS key. The standard asymmetric encryption algorithms and HMAC algorithms that KMS uses do not support an encryption context.</p> <p>An <i>encryption context</i> is a collection of non-secret key-value pairs that represent additional authenticated data. When you use an encryption context to encrypt data, you must specify the same (an exact case-sensitive match) encryption context to decrypt the data. An encryption context is supported only on operations with symmetric encryption KMS keys. On operations with symmetric encryption KMS keys, an encryption context is optional, but it is strongly recommended.</p> <p>For more information, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/encrypt_context.html">Encryption context</a> in the <i>Key Management Service Developer Guide</i>.</p>
        grant_tokens: <p>A list of grant tokens. </p> <p>Use a grant token when your permission to call this operation comes from a new grant that has not yet achieved <i>eventual consistency</i>. For more information, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/grants.html#grant_token">Grant token</a> and <a href="https://docs.aws.amazon.com/kms/latest/developerguide/using-grant-token.html">Using a grant token</a> in the <i>Key Management Service Developer Guide</i>.</p>
        key_id: <p>Specifies the KMS key that KMS uses to decrypt the ciphertext.</p> <p>Enter a key ID of the KMS key that was used to encrypt the ciphertext. If you identify a different KMS key, the <code>Decrypt</code> operation throws an <code>IncorrectKeyException</code>.</p> <p>This parameter is required only when the ciphertext was encrypted under an asymmetric KMS key or when <code>DryRun</code> is <code>true</code> and <code>DryRunModifiers</code> is set to <code>IGNORE_CIPHERTEXT</code>. If you used a symmetric encryption KMS key, KMS can get the KMS key from metadata that it adds to the symmetric ciphertext blob. However, it is always recommended as a best practice. This practice ensures that you use the KMS key that you intend.</p> <p>To specify a KMS key, use its key ID, key ARN, alias name, or alias ARN. When using an alias name, prefix it with <code>"alias/"</code>. To specify a KMS key in a different Amazon Web Services account, you should use the key ARN or alias ARN.</p> <p>For example:</p> <ul> <li> <p>Key ID: <code>1234abcd-12ab-34cd-56ef-1234567890ab</code> </p> </li> <li> <p>Key ARN: <code>arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab</code> </p> </li> <li> <p>Alias name: <code>alias/ExampleAlias</code> </p> </li> <li> <p>Alias ARN: <code>arn:aws:kms:us-east-2:111122223333:alias/ExampleAlias</code> </p> </li> </ul> <p>To get the key ID and key ARN for a KMS key, use <a>ListKeys</a> or <a>DescribeKey</a>. To get the alias name and alias ARN, use <a>ListAliases</a>.</p>
        encryption_algorithm: <p>Specifies the encryption algorithm that will be used to decrypt the ciphertext. Specify the same algorithm that was used to encrypt the data. If you specify a different algorithm, the <code>Decrypt</code> operation fails.</p> <p>This parameter is required only when the ciphertext was encrypted under an asymmetric KMS key. The default value, <code>SYMMETRIC_DEFAULT</code>, represents the only supported algorithm that is valid for symmetric encryption KMS keys.</p>
        recipient: <p>A signed <a href="https://docs.aws.amazon.com/enclaves/latest/user/nitro-enclave-concepts.html#term-attestdoc">attestation document</a> from an Amazon Web Services Nitro enclave or NitroTPM, and the encryption algorithm to use with the public key in the attestation document. The only valid encryption algorithm is <code>RSAES_OAEP_SHA_256</code>. </p> <p>This parameter supports the <a href="https://docs.aws.amazon.com/enclaves/latest/user/developing-applications.html#sdk">Amazon Web Services Nitro Enclaves SDK</a> or any Amazon Web Services SDK for Amazon Web Services Nitro Enclaves. It supports any Amazon Web Services SDK for Amazon Web Services NitroTPM. </p> <p>When you use this parameter, instead of returning the plaintext data, KMS encrypts the plaintext data with the public key in the attestation document, and returns the resulting ciphertext in the <code>CiphertextForRecipient</code> field in the response. This ciphertext can be decrypted only with the private key in the attested environment. The <code>Plaintext</code> field in the response is null or empty.</p> <p>For information about the interaction between KMS and Amazon Web Services Nitro Enclaves or Amazon Web Services NitroTPM, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/cryptographic-attestation.html">Cryptographic attestation support in KMS</a> in the <i>Key Management Service Developer Guide</i>.</p>
        dry_run: <p>Checks if your request will succeed. <code>DryRun</code> is an optional parameter. </p> <p>To learn more about how to use this parameter, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/testing-permissions.html">Testing your permissions</a> in the <i>Key Management Service Developer Guide</i>.</p>
        dry_run_modifiers: <p>Specifies the modifiers to apply to the dry run operation. <code>DryRunModifiers</code> is an optional parameter that only applies when <code>DryRun</code> is set to <code>true</code>.</p> <p>When set to <code>IGNORE_CIPHERTEXT</code>, KMS performs only authorization validation without ciphertext validation. This allows you to test permissions without requiring a valid ciphertext blob.</p> <p>To learn more about how to use this parameter, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/testing-permissions.html">Testing your permissions</a> in the <i>Key Management Service Developer Guide</i>.</p>

    Raises:
        capo_kms.errors.dependency_timeout_exception.DependencyTimeoutException: <p>The system timed out while trying to fulfill the request. You can retry the request.</p>
        capo_kms.errors.disabled_exception.DisabledException: <p>The request was rejected because the specified KMS key is not enabled.</p>
        capo_kms.errors.dry_run_operation_exception.DryRunOperationException: <p> The request was rejected because the DryRun parameter was specified. </p>
        capo_kms.errors.incorrect_key_exception.IncorrectKeyException: <p>The request was rejected because the specified KMS key cannot decrypt the data. The <code>KeyId</code> in a <a>Decrypt</a> request and the <code>SourceKeyId</code> in a <a>ReEncrypt</a> request must identify the same KMS key that was used to encrypt the ciphertext.</p>
        capo_kms.errors.invalid_ciphertext_exception.InvalidCiphertextException: <p>From the <a>Decrypt</a> or <a>ReEncrypt</a> operation, the request was rejected because the specified ciphertext, or additional authenticated data incorporated into the ciphertext, such as the encryption context, is corrupted, missing, or otherwise invalid.</p> <p>From the <a>ImportKeyMaterial</a> operation, the request was rejected because KMS could not decrypt the encrypted (wrapped) key material. </p>
        capo_kms.errors.invalid_grant_token_exception.InvalidGrantTokenException: <p>The request was rejected because the specified grant token is not valid.</p>
        capo_kms.errors.invalid_key_usage_exception.InvalidKeyUsageException: <p>The request was rejected for one of the following reasons: </p> <ul> <li> <p>The <code>KeyUsage</code> value of the KMS key is incompatible with the API operation.</p> </li> <li> <p>The encryption algorithm or signing algorithm specified for the operation is incompatible with the type of key material in the KMS key <code>(KeySpec</code>).</p> </li> </ul> <p>For encrypting, decrypting, re-encrypting, and generating data keys, the <code>KeyUsage</code> must be <code>ENCRYPT_DECRYPT</code>. For signing and verifying messages, the <code>KeyUsage</code> must be <code>SIGN_VERIFY</code>. For generating and verifying message authentication codes (MACs), the <code>KeyUsage</code> must be <code>GENERATE_VERIFY_MAC</code>. For deriving key agreement secrets, the <code>KeyUsage</code> must be <code>KEY_AGREEMENT</code>. To find the <code>KeyUsage</code> of a KMS key, use the <a>DescribeKey</a> operation.</p> <p>To find the encryption or signing algorithms supported for a particular KMS key, use the <a>DescribeKey</a> operation.</p>
        capo_kms.errors.key_unavailable_exception.KeyUnavailableException: <p>The request was rejected because the specified KMS key was not available. You can retry the request.</p>
        capo_kms.errors.kms_internal_exception.KMSInternalException: <p>The request was rejected because an internal exception occurred. The request can be retried.</p>
        capo_kms.errors.kms_invalid_state_exception.KMSInvalidStateException: <p>The request was rejected because the state of the specified resource is not valid for this request.</p> <p>This exceptions means one of the following:</p> <ul> <li> <p>The key state of the KMS key is not compatible with the operation. </p> <p>To find the key state, use the <a>DescribeKey</a> operation. For more information about which key states are compatible with each KMS operation, see <a href="https://docs.aws.amazon.com/kms/latest/developerguide/key-state.html">Key states of KMS keys</a> in the <i> <i>Key Management Service Developer Guide</i> </i>.</p> </li> <li> <p>For cryptographic operations on KMS keys in custom key stores, this exception represents a general failure with many possible causes. To identify the cause, see the error message that accompanies the exception.</p> </li> </ul>
        capo_kms.errors.not_found_exception.NotFoundException: <p>The request was rejected because the specified entity or resource could not be found.</p>
        capo_kms.errors.UnknownServiceError: The service returned an error code this client does not model.

    Examples:
        To decrypt data with an asymmetric encryption KMS key
        The following example decrypts data that was encrypted with an asymmetric encryption KMS key. When the KMS encryption key is asymmetric, you must specify the KMS key ID and the encryption algorithm that was used to encrypt the data.

        >>> client.decrypt(ciphertext_blob='<binary data>', key_id='0987dcba-09fe-87dc-65ba-ab0987654321', encryption_algorithm='RSAES_OAEP_SHA_256')
        To decrypt data with a symmetric encryption KMS key
        The following example decrypts data that was encrypted with a symmetric encryption KMS key. The KeyId is not required when decrypting with a symmetric encryption key, but it is a best practice.

        >>> client.decrypt(ciphertext_blob='<binary data>', key_id='arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab')
    """

    def _handler(
        req: "OperationRequest[capo_kms.types.decrypt_request.DecryptRequest]",
    ) -> OperationResponse["capo_kms.types.decrypt_response.DecryptResponse"]:
        import capo_kms._operations.trent_service.decrypt

        output, http_response = capo_kms._operations.trent_service.decrypt.decrypt(
            req.options, req.input
        )
        return OperationResponse(output=output, response=http_response)

    def _redact_output(
        output: "capo_kms.types.decrypt_response.DecryptResponse",
    ) -> dict[str, Any]:
        import capo_kms.types.decrypt_response

        return capo_kms.types.decrypt_response.redact_sensitive(output)

    interceptors_, options_ = self.operation_options(
        config_overrides, OperationLogging("Decrypt", redact_output=_redact_output)
    )
    input_: capo_kms.types.decrypt_request.DecryptRequest = {}
    if ciphertext_blob is not None:
        input_["ciphertext_blob"] = ciphertext_blob
    if encryption_context is not None:
        input_["encryption_context"] = encryption_context
    if grant_tokens is not None:
        input_["grant_tokens"] = grant_tokens
    if key_id is not None:
        input_["key_id"] = key_id
    if encryption_algorithm is not None:
        input_["encryption_algorithm"] = encryption_algorithm
    if recipient is not None:
        input_["recipient"] = recipient
    if dry_run is not None:
        input_["dry_run"] = dry_run
    if dry_run_modifiers is not None:
        input_["dry_run_modifiers"] = dry_run_modifiers

    response = execute_pipeline(
        OperationRequest(input=input_, options=options_),
        handler=_handler,
        interceptors=list(interceptors_),
    )
    response.response.close()
    return response.output