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paws.security.identity (version 0.7.0)

kms_sign: Creates a digital signature for a message or message digest by using the private key in an asymmetric signing KMS key

Description

Creates a digital signature for a message or message digest by using the private key in an asymmetric signing KMS key. To verify the signature, use the verify operation, or use the public key in the same asymmetric KMS key outside of KMS. For information about asymmetric KMS keys, see Asymmetric KMS keys in the Key Management Service Developer Guide.

See https://www.paws-r-sdk.com/docs/kms_sign/ for full documentation.

Usage

kms_sign(
  KeyId,
  Message,
  MessageType = NULL,
  GrantTokens = NULL,
  SigningAlgorithm,
  DryRun = NULL
)

Arguments

KeyId

[required] Identifies an asymmetric KMS key. KMS uses the private key in the asymmetric KMS key to sign the message. The KeyUsage type of the KMS key must be SIGN_VERIFY. To find the KeyUsage of a KMS key, use the describe_key operation.

To specify a KMS key, use its key ID, key ARN, alias name, or alias ARN. When using an alias name, prefix it with "alias/". To specify a KMS key in a different Amazon Web Services account, you must use the key ARN or alias ARN.

For example:

  • Key ID: 1234abcd-12ab-34cd-56ef-1234567890ab

  • Key ARN: arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab

  • Alias name: alias/ExampleAlias

  • Alias ARN: arn:aws:kms:us-east-2:111122223333:alias/ExampleAlias

To get the key ID and key ARN for a KMS key, use list_keys or describe_key. To get the alias name and alias ARN, use list_aliases.

Message

[required] Specifies the message or message digest to sign. Messages can be 0-4096 bytes. To sign a larger message, provide a message digest.

If you provide a message digest, use the DIGEST value of MessageType to prevent the digest from being hashed again while signing.

MessageType

Tells KMS whether the value of the Message parameter should be hashed as part of the signing algorithm. Use RAW for unhashed messages; use DIGEST for message digests, which are already hashed.

When the value of MessageType is RAW, KMS uses the standard signing algorithm, which begins with a hash function. When the value is DIGEST, KMS skips the hashing step in the signing algorithm.

Use the DIGEST value only when the value of the Message parameter is a message digest. If you use the DIGEST value with an unhashed message, the security of the signing operation can be compromised.

When the value of MessageTypeis DIGEST, the length of the Message value must match the length of hashed messages for the specified signing algorithm.

You can submit a message digest and omit the MessageType or specify RAW so the digest is hashed again while signing. However, this can cause verification failures when verifying with a system that assumes a single hash.

The hashing algorithm in that sign uses is based on the SigningAlgorithm value.

  • Signing algorithms that end in SHA_256 use the SHA_256 hashing algorithm.

  • Signing algorithms that end in SHA_384 use the SHA_384 hashing algorithm.

  • Signing algorithms that end in SHA_512 use the SHA_512 hashing algorithm.

  • SM2DSA uses the SM3 hashing algorithm. For details, see Offline verification with SM2 key pairs.

GrantTokens

A list of grant tokens.

Use a grant token when your permission to call this operation comes from a new grant that has not yet achieved eventual consistency. For more information, see Grant token and Using a grant token in the Key Management Service Developer Guide.

SigningAlgorithm

[required] Specifies the signing algorithm to use when signing the message.

Choose an algorithm that is compatible with the type and size of the specified asymmetric KMS key. When signing with RSA key pairs, RSASSA-PSS algorithms are preferred. We include RSASSA-PKCS1-v1_5 algorithms for compatibility with existing applications.

DryRun

Checks if your request will succeed. DryRun is an optional parameter.

To learn more about how to use this parameter, see Testing your KMS API calls in the Key Management Service Developer Guide.