Container for the parameters to the Verify operation. Verifies a digital signature that was generated by the Sign operation.
Verification confirms that an authorized user signed the message with the specified
KMS key and signing algorithm, and the message hasn't changed since it was signed.
If the signature is verified, the value of the SignatureValid field in the
response is True. If the signature verification fails, the Verify operation
fails with an KMSInvalidSignatureException exception.
A digital signature is generated by using the private key in an asymmetric KMS key. The signature is verified by using the public key in the same asymmetric KMS key. For information about asymmetric KMS keys, see Asymmetric KMS keys in the Key Management Service Developer Guide.
To use the Verify operation, specify the same asymmetric KMS key, message,
and signing algorithm that were used to produce the signature. The message type does
not need to be the same as the one used for signing, but it must indicate whether
the value of the Message parameter should be hashed as part of the verification
process.
You can also verify the digital signature by using the public key of the KMS key outside
of KMS. Use the GetPublicKey operation to download the public key in the asymmetric
KMS key and then use the public key to verify the signature outside of KMS. The advantage
of using the Verify operation is that it is performed within KMS. As a result,
it's easy to call, the operation is performed within the FIPS boundary, it is logged
in CloudTrail, and you can use key policy and IAM policy to determine who is authorized
to use the KMS key to verify signatures.
To verify a signature outside of KMS with an SM2 public key (China Regions only),
you must specify the distinguishing ID. By default, KMS uses 1234567812345678
as the distinguishing ID. For more information, see Offline
verification with SM2 key pairs.
The KMS key that you use for this operation must be in a compatible key state. For details, see Key states of KMS keys in the Key Management Service Developer Guide.
Cross-account use: Yes. To perform this operation with a KMS key in a different
Amazon Web Services account, specify the key ARN or alias ARN in the value of the
KeyId parameter.
Required permissions: kms:Verify (key policy)
Related operations: Sign
Eventual consistency: The KMS API follows an eventual consistency model. For more information, see KMS eventual consistency.
Inheritance Hierarchy
Amazon.Runtime.AmazonWebServiceRequest
Amazon.KeyManagementService.AmazonKeyManagementServiceRequest
Amazon.KeyManagementService.Model.VerifyRequest
Namespace: Amazon.KeyManagementService.Model
Assembly: AWSSDK.KeyManagementService.dll
Version: 3.x.y.z
Syntax
public class VerifyRequest : AmazonKeyManagementServiceRequest IAmazonWebServiceRequest
The VerifyRequest type exposes the following members
Constructors
| Name | Description | |
|---|---|---|
|
VerifyRequest() |
Properties
| Name | Type | Description | |
|---|---|---|---|
|
|
DryRun | System.Boolean |
Gets and sets the property DryRun.
Checks if your request will succeed. To learn more about how to use this parameter, see Testing your KMS API calls in the Key Management Service Developer Guide. |
|
|
GrantTokens | System.Collections.Generic.List<System.String> |
Gets and sets the property 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. |
|
|
KeyId | System.String |
Gets and sets the property KeyId. Identifies the asymmetric KMS key that will be used to verify the signature. This must be the same KMS key that was used to generate the signature. If you specify a different KMS key, the signature verification fails.
To specify a KMS key, use its key ID, key ARN, alias name, or alias ARN. When using
an alias name, prefix it with For example:
To get the key ID and key ARN for a KMS key, use ListKeys or DescribeKey. To get the alias name and alias ARN, use ListAliases. |
|
|
Message | System.IO.MemoryStream |
Gets and sets the property Message.
Specifies the message that was signed. You can submit a raw message of up to 4096
bytes, or a hash digest of the message. If you submit a digest, use the If the message specified here is different from the message that was signed, the signature verification fails. A message and its hash digest are considered to be the same message. |
|
|
MessageType | Amazon.KeyManagementService.MessageType |
Gets and sets the property MessageType.
Tells KMS whether the value of the
When the value of
Use the
When the value of
You can submit a message digest and omit the
The hashing algorithm in that
|
|
|
Signature | System.IO.MemoryStream |
Gets and sets the property Signature.
The signature that the |
|
|
SigningAlgorithm | Amazon.KeyManagementService.SigningAlgorithmSpec |
Gets and sets the property SigningAlgorithm. The signing algorithm that was used to sign the message. If you submit a different algorithm, the signature verification fails. |
Examples
This operation uses the public key in an elliptic curve (ECC) asymmetric key to verify a digital signature within AWS KMS.
To use an asymmetric KMS key to verify a digital signature
var client = new AmazonKeyManagementServiceClient();
var response = client.Verify(new VerifyRequest
{
KeyId = "alias/ECC_signing_key", // The asymmetric KMS key to be used to verify the digital signature. This example uses an alias to identify the KMS key.
Message = new MemoryStream(<message to be verified>), // The message that was signed.
MessageType = "RAW", // Indicates whether the message is RAW or a DIGEST.
Signature = new MemoryStream(<binary data>), // The signature to be verified.
SigningAlgorithm = "ECDSA_SHA_384" // The signing algorithm to be used to verify the signature.
});
string keyId = response.KeyId; // The key ARN of the asymmetric KMS key that was used to verify the digital signature.
bool signatureValid = response.SignatureValid; // A value of 'true' Indicates that the signature was verified. If verification fails, the call to Verify fails.
string signingAlgorithm = response.SigningAlgorithm; // The signing algorithm that was used to verify the signature.
This operation uses the public key in an RSA asymmetric signing key pair to verify the digital signature of a message digest. Hashing a message into a digest before sending it to KMS lets you verify messages that exceed the 4096-byte message size limit. To indicate that the value of Message is a digest, use the MessageType parameter
To use an asymmetric KMS key to verify a digital signature on a message digest
var client = new AmazonKeyManagementServiceClient();
var response = client.Verify(new VerifyRequest
{
KeyId = "arn:aws:kms:us-east-2:111122223333:key/0987dcba-09fe-87dc-65ba-ab0987654321", // The asymmetric KMS key to be used to verify the digital signature. This example uses an alias to identify the KMS key.
Message = new MemoryStream(<message digest to be verified>), // The message that was signed.
MessageType = "DIGEST", // Indicates whether the message is RAW or a DIGEST. When it is RAW, KMS hashes the message before signing. When it is DIGEST, KMS skips the hashing step and signs the Message value.
Signature = new MemoryStream(<binary data>), // The signature to be verified.
SigningAlgorithm = "RSASSA_PSS_SHA_512" // The signing algorithm to be used to verify the signature.
});
string keyId = response.KeyId; // The key ARN of the asymmetric KMS key that was used to verify the digital signature.
bool signatureValid = response.SignatureValid; // A value of 'true' Indicates that the signature was verified. If verification fails, the call to Verify fails.
string signingAlgorithm = response.SigningAlgorithm; // The signing algorithm that was used to verify the signature.
Version Information
.NET Core App:
Supported in: 3.1
.NET Standard:
Supported in: 2.0
.NET Framework:
Supported in: 4.5, 4.0, 3.5