重新加密数据

本主题介绍如何使用 Cloud Key Management Service 对称密钥重新加密数据。 您可以根据非对称密钥调整这些示例。 如果您怀疑存在未经授权使用密钥的情况，则应当重新加密受该密钥保护的数据，然后停用或安排销毁先前的密钥版本。

准备工作

此场景需要以下条件。

• 您已使用 Cloud KMS 加密了数据。

• 用于加密的密钥版本并非处于已停用、计划销毁或已销毁状态。您使用此密钥版本对已加密的数据进行解密。

• 你已经对密钥进行了轮替。密钥轮替会创建新的主密钥版本。您使用新的主密钥版本重新加密数据。

注意：密钥轮替不会使用新生成的密钥版本重新加密已加密的数据。您需要自己重新加密数据，如本主题中所述。

使用非对称密钥重新加密数据

本主题中的示例展示了如何使用对称密钥重新加密数据。 当您使用对称密钥时，Cloud KMS 会自动推断用于解密的密钥版本。使用非对称密钥时，您必须指定密钥版本。

• 按照 Google Cloud CLI 的使用说明操作时，请始终添加 --version 标志。
• 按照 API 的使用说明操作时，请使用 CryptoKeyVersions 而不是 CryptoKeys。您可以详细了解如何使用非对称密钥对数据进行加密和解密。

使用非对称密钥重新加密数据的工作流程类似于本主题中介绍的工作流程。

重新加密数据工作流程

使用以下步骤，重新加密数据并停用或安排销毁最初用于加密的密钥版本。

1. 使用先前的密钥版本解密数据

2. 使用新的主密钥版本重新加密数据

3. 停用或安排销毁先前的密钥版本

使用先前的密钥版本解密数据

Cloud KMS 会自动使用正确的密钥版本解密数据，前提是该密钥版本并非处于已停用、已安排销毁或已销毁状态。以下示例显示了如何解密数据。 示例与加密和解密使用的解密代码相同。

gcloud

如需在命令行上使用 Cloud KMS，请先安装或升级到最新版本的 Google Cloud CLI。

gcloud kms decrypt \
    --key KEY_NAME \
    --keyring KEY_RING \
    --location LOCATION  \
    --ciphertext-file FILE_TO_DECRYPT \
    --plaintext-file DECRYPTED_OUTPUT

替换以下内容：

• KEY_NAME：您要用于解密的密钥的名称。
• KEY_RING：包含密钥的密钥环的名称。
• LOCATION：包含密钥环的 Cloud KMS 位置。
• FILE_TO_DECRYPT：要解密的文件所在的路径。
• DECRYPTED_OUTPUT：您要将解密后的输出保存到的路径。

如需了解所有标志和可能值，请使用 --help 标志运行命令。

C#

要运行此代码，请先设置 C# 开发环境并安装 Cloud KMS C# SDK。

using Google.Cloud.Kms.V1;
using Google.Protobuf;
using System.Text;

public class DecryptSymmetricSample
{
    public string DecryptSymmetric(
      string projectId = "my-project", string locationId = "us-east1", string keyRingId = "my-key-ring", string keyId = "my-key",
      byte[] ciphertext = null)
    {
        // Create the client.
        KeyManagementServiceClient client = KeyManagementServiceClient.Create();

        // Build the key name.
        CryptoKeyName keyName = new CryptoKeyName(projectId, locationId, keyRingId, keyId);

        // Call the API.
        DecryptResponse result = client.Decrypt(keyName, ByteString.CopyFrom(ciphertext));

        // Get the plaintext. Cryptographic plaintexts and ciphertexts are
        // always byte arrays.
        byte[] plaintext = result.Plaintext.ToByteArray();

        // Return the result.
        return Encoding.UTF8.GetString(plaintext);
    }
}

Go

要运行此代码，请先设置 Go 开发环境并安装 Cloud KMS Go SDK。

import (
	"context"
	"fmt"
	"hash/crc32"
	"io"

	kms "cloud.google.com/go/kms/apiv1"
	"cloud.google.com/go/kms/apiv1/kmspb"
	"google.golang.org/protobuf/types/known/wrapperspb"
)

// decryptSymmetric will decrypt the input ciphertext bytes using the specified symmetric key.
func decryptSymmetric(w io.Writer, name string, ciphertext []byte) error {
	// name := "projects/my-project/locations/us-east1/keyRings/my-key-ring/cryptoKeys/my-key"
	// ciphertext := []byte("...")  // result of a symmetric encryption call

	// Create the client.
	ctx := context.Background()
	client, err := kms.NewKeyManagementClient(ctx)
	if err != nil {
		return fmt.Errorf("failed to create kms client: %w", err)
	}
	defer client.Close()

	// Optional, but recommended: Compute ciphertext's CRC32C.
	crc32c := func(data []byte) uint32 {
		t := crc32.MakeTable(crc32.Castagnoli)
		return crc32.Checksum(data, t)
	}
	ciphertextCRC32C := crc32c(ciphertext)

	// Build the request.
	req := &kmspb.DecryptRequest{
		Name:             name,
		Ciphertext:       ciphertext,
		CiphertextCrc32C: wrapperspb.Int64(int64(ciphertextCRC32C)),
	}

	// Call the API.
	result, err := client.Decrypt(ctx, req)
	if err != nil {
		return fmt.Errorf("failed to decrypt ciphertext: %w", err)
	}

	// Optional, but recommended: perform integrity verification on result.
	// For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
	// https://cloud.google.com/kms/docs/data-integrity-guidelines
	if int64(crc32c(result.Plaintext)) != result.PlaintextCrc32C.Value {
		return fmt.Errorf("Decrypt: response corrupted in-transit")
	}

	fmt.Fprintf(w, "Decrypted plaintext: %s", result.Plaintext)
	return nil
}

Java

要运行此代码，请先设置 Java 开发环境并安装 Cloud KMS Java SDK。

import com.google.cloud.kms.v1.CryptoKeyName;
import com.google.cloud.kms.v1.DecryptResponse;
import com.google.cloud.kms.v1.KeyManagementServiceClient;
import com.google.protobuf.ByteString;
import java.io.IOException;

public class DecryptSymmetric {

  public void decryptSymmetric() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-project-id";
    String locationId = "us-east1";
    String keyRingId = "my-key-ring";
    String keyId = "my-key";
    byte[] ciphertext = null;
    decryptSymmetric(projectId, locationId, keyRingId, keyId, ciphertext);
  }

  // Decrypt data that was encrypted using a symmetric key.
  public void decryptSymmetric(
      String projectId, String locationId, String keyRingId, String keyId, byte[] ciphertext)
      throws IOException {
    // Initialize client that will be used to send requests. This client only
    // needs to be created once, and can be reused for multiple requests. After
    // completing all of your requests, call the "close" method on the client to
    // safely clean up any remaining background resources.
    try (KeyManagementServiceClient client = KeyManagementServiceClient.create()) {
      // Build the key version name from the project, location, key ring, and
      // key.
      CryptoKeyName keyName = CryptoKeyName.of(projectId, locationId, keyRingId, keyId);

      // Decrypt the response.
      DecryptResponse response = client.decrypt(keyName, ByteString.copyFrom(ciphertext));
      System.out.printf("Plaintext: %s%n", response.getPlaintext().toStringUtf8());
    }
  }
}

Node.js

要运行此代码，请先设置 Node.js 开发环境并安装 Cloud KMS Node.js SDK。

//
// TODO(developer): Uncomment these variables before running the sample.
//
// const projectId = 'my-project';
// const locationId = 'us-east1';
// const keyRingId = 'my-key-ring';
// const keyId = 'my-key';
// Ciphertext must be either a Buffer object or a base-64 encoded string
// const ciphertext = Buffer.from('...');

// Imports the Cloud KMS library
const {KeyManagementServiceClient} = require('@google-cloud/kms');

// Instantiates a client
const client = new KeyManagementServiceClient();

// Build the key name
const keyName = client.cryptoKeyPath(projectId, locationId, keyRingId, keyId);

// Optional, but recommended: compute ciphertext's CRC32C.
const crc32c = require('fast-crc32c');
const ciphertextCrc32c = crc32c.calculate(ciphertext);

async function decryptSymmetric() {
  const [decryptResponse] = await client.decrypt({
    name: keyName,
    ciphertext: ciphertext,
    ciphertextCrc32c: {
      value: ciphertextCrc32c,
    },
  });

  // Optional, but recommended: perform integrity verification on decryptResponse.
  // For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
  // https://cloud.google.com/kms/docs/data-integrity-guidelines
  if (
    crc32c.calculate(decryptResponse.plaintext) !==
    Number(decryptResponse.plaintextCrc32c.value)
  ) {
    throw new Error('Decrypt: response corrupted in-transit');
  }

  const plaintext = decryptResponse.plaintext.toString();

  console.log(`Plaintext: ${plaintext}`);
  return plaintext;
}

return decryptSymmetric();

PHP

如需运行此代码，请先了解如何在 Google Cloud上使用 PHP 并安装 Cloud KMS PHP SDK。

use Google\Cloud\Kms\V1\Client\KeyManagementServiceClient;
use Google\Cloud\Kms\V1\DecryptRequest;

function decrypt_symmetric(
    string $projectId = 'my-project',
    string $locationId = 'us-east1',
    string $keyRingId = 'my-key-ring',
    string $keyId = 'my-key',
    string $ciphertext = '...'
) {
    // Create the Cloud KMS client.
    $client = new KeyManagementServiceClient();

    // Build the key name.
    $keyName = $client->cryptoKeyName($projectId, $locationId, $keyRingId, $keyId);

    // Call the API.
    $decryptRequest = (new DecryptRequest())
        ->setName($keyName)
        ->setCiphertext($ciphertext);
    $decryptResponse = $client->decrypt($decryptRequest);
    printf('Plaintext: %s' . PHP_EOL, $decryptResponse->getPlaintext());

    return $decryptResponse;
}

Python

要运行此代码，请先设置 Python 开发环境并安装 Cloud KMS Python SDK。

from google.cloud import kms


def decrypt_symmetric(
    project_id: str, location_id: str, key_ring_id: str, key_id: str, ciphertext: bytes
) -> kms.DecryptResponse:
    """
    Decrypt the ciphertext using the symmetric key

    Args:
        project_id (string): Google Cloud project ID (e.g. 'my-project').
        location_id (string): Cloud KMS location (e.g. 'us-east1').
        key_ring_id (string): ID of the Cloud KMS key ring (e.g. 'my-key-ring').
        key_id (string): ID of the key to use (e.g. 'my-key').
        ciphertext (bytes): Encrypted bytes to decrypt.

    Returns:
        DecryptResponse: Response including plaintext.

    """

    # Create the client.
    client = kms.KeyManagementServiceClient()

    # Build the key name.
    key_name = client.crypto_key_path(project_id, location_id, key_ring_id, key_id)

    # Optional, but recommended: compute ciphertext's CRC32C.
    # See crc32c() function defined below.
    ciphertext_crc32c = crc32c(ciphertext)

    # Call the API.
    decrypt_response = client.decrypt(
        request={
            "name": key_name,
            "ciphertext": ciphertext,
            "ciphertext_crc32c": ciphertext_crc32c,
        }
    )

    # Optional, but recommended: perform integrity verification on decrypt_response.
    # For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
    # https://cloud.google.com/kms/docs/data-integrity-guidelines
    if not decrypt_response.plaintext_crc32c == crc32c(decrypt_response.plaintext):
        raise Exception(
            "The response received from the server was corrupted in-transit."
        )
    # End integrity verification

    print(f"Plaintext: {decrypt_response.plaintext!r}")
    return decrypt_response


def crc32c(data: bytes) -> int:
    """
    Calculates the CRC32C checksum of the provided data.
    Args:
        data: the bytes over which the checksum should be calculated.
    Returns:
        An int representing the CRC32C checksum of the provided bytes.
    """
    import crcmod  # type: ignore

    crc32c_fun = crcmod.predefined.mkPredefinedCrcFun("crc-32c")
    return crc32c_fun(data)

Ruby

要运行此代码，请先设置 Ruby 开发环境并安装 Cloud KMS Ruby SDK。

# TODO(developer): uncomment these values before running the sample.
# project_id  = "my-project"
# location_id = "us-east1"
# key_ring_id = "my-key-ring"
# key_id      = "my-key"
# ciphertext  = "..."

# Require the library.
require "google/cloud/kms"

# Create the client.
client = Google::Cloud::Kms.key_management_service

# Build the parent key name.
key_name = client.crypto_key_path project:    project_id,
                                  location:   location_id,
                                  key_ring:   key_ring_id,
                                  crypto_key: key_id

# Call the API.
response = client.decrypt name: key_name, ciphertext: ciphertext
puts "Plaintext: #{response.plaintext}"

API

这些示例使用 curl 作为 HTTP 客户端来演示如何使用 API。如需详细了解访问权限控制，请参阅访问 Cloud KMS API。

从 Cloud KMS 中以 JSON 格式返回的解密后文本使用 base64 进行编码。

提示：您可以使用 Linux 或 macOS 上的 base64 命令或 Windows 上的 Base64.exe 命令对数据进行 base64 编码或解码。编程语言和脚本语言通常包含用于 base64 编码的库。如需查看命令行示例，请参阅 Cloud Vision API 文档中的 Base64 编码。

要对加密数据进行解密，请发出 POST 请求并提供相应的项目和密钥信息，并在请求正文的 ciphertext 字段中指定要解密的加密文本（也称为密文）。

curl "https://cloudkms.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/keyRings/KEY_RING/cryptoKeys/KEY_NAME:decrypt" \
  --request "POST" \
  --header "authorization: Bearer TOKEN" \
  --header "content-type: application/json" \
  --data "{\"ciphertext\": \"ENCRYPTED_DATA\"}"

替换以下内容：

• PROJECT_ID：包含您要用于解密的密钥环和密钥的项目的 ID。
• LOCATION：包含密钥环的 Cloud KMS 位置。
• KEY_RING：包含您要用于解密的密钥的密钥环。
• KEY_NAME：您要用于解密的密钥的名称。
• ENCRYPTED_DATA：您要解密的加密数据。

以下是包含 base64 编码数据的示例载荷：

{
  "ciphertext": "CiQAhMwwBo61cHas7dDgifrUFs5zNzBJ2uZtVFq4ZPEl6fUVT4kSmQ...",
}

使用新的主密钥版本重新加密数据

Cloud KMS 自动使用新的主密钥版本来加密数据。以下示例显示了如何加密数据。示例与加密和解密中使用的加密代码相同。

gcloud

如需在命令行上使用 Cloud KMS，请先安装或升级到最新版本的 Google Cloud CLI。

gcloud kms encrypt \
    --key KEY_NAME \
    --keyring KEY_RING \
    --location LOCATION  \
    --plaintext-file FILE_TO_ENCRYPT \
    --ciphertext-file ENCRYPTED_OUTPUT

替换以下内容：

• KEY_NAME：您要用于加密的密钥的名称。
• KEY_RING：包含密钥的密钥环的名称。
• LOCATION：包含密钥环的 Cloud KMS 位置。
• FILE_TO_ENCRYPT：您要加密的文件的路径。
• ENCRYPTED_OUTPUT：您要将加密输出保存到的路径。

如需了解所有标志和可能值，请使用 --help 标志运行命令。

C#

要运行此代码，请先设置 C# 开发环境并安装 Cloud KMS C# SDK。

using Google.Cloud.Kms.V1;
using Google.Protobuf;
using System.Text;

public class EncryptSymmetricSample
{
    public byte[] EncryptSymmetric(
      string projectId = "my-project", string locationId = "us-east1", string keyRingId = "my-key-ring", string keyId = "my-key",
      string message = "Sample message")
    {
        // Create the client.
        KeyManagementServiceClient client = KeyManagementServiceClient.Create();

        // Build the key name.
        CryptoKeyName keyName = new CryptoKeyName(projectId, locationId, keyRingId, keyId);

        // Convert the message into bytes. Cryptographic plaintexts and
        // ciphertexts are always byte arrays.
        byte[] plaintext = Encoding.UTF8.GetBytes(message);

        // Call the API.
        EncryptResponse result = client.Encrypt(keyName, ByteString.CopyFrom(plaintext));

        // Return the ciphertext.
        return result.Ciphertext.ToByteArray();
    }
}

Go

要运行此代码，请先设置 Go 开发环境并安装 Cloud KMS Go SDK。

import (
	"context"
	"fmt"
	"hash/crc32"
	"io"

	kms "cloud.google.com/go/kms/apiv1"
	"cloud.google.com/go/kms/apiv1/kmspb"
	"google.golang.org/protobuf/types/known/wrapperspb"
)

// encryptSymmetric encrypts the input plaintext with the specified symmetric
// Cloud KMS key.
func encryptSymmetric(w io.Writer, name string, message string) error {
	// name := "projects/my-project/locations/us-east1/keyRings/my-key-ring/cryptoKeys/my-key"
	// message := "Sample message"

	// Create the client.
	ctx := context.Background()
	client, err := kms.NewKeyManagementClient(ctx)
	if err != nil {
		return fmt.Errorf("failed to create kms client: %w", err)
	}
	defer client.Close()

	// Convert the message into bytes. Cryptographic plaintexts and
	// ciphertexts are always byte arrays.
	plaintext := []byte(message)

	// Optional but recommended: Compute plaintext's CRC32C.
	crc32c := func(data []byte) uint32 {
		t := crc32.MakeTable(crc32.Castagnoli)
		return crc32.Checksum(data, t)
	}
	plaintextCRC32C := crc32c(plaintext)

	// Build the request.
	req := &kmspb.EncryptRequest{
		Name:            name,
		Plaintext:       plaintext,
		PlaintextCrc32C: wrapperspb.Int64(int64(plaintextCRC32C)),
	}

	// Call the API.
	result, err := client.Encrypt(ctx, req)
	if err != nil {
		return fmt.Errorf("failed to encrypt: %w", err)
	}

	// Optional, but recommended: perform integrity verification on result.
	// For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
	// https://cloud.google.com/kms/docs/data-integrity-guidelines
	if result.VerifiedPlaintextCrc32C == false {
		return fmt.Errorf("Encrypt: request corrupted in-transit")
	}
	if int64(crc32c(result.Ciphertext)) != result.CiphertextCrc32C.Value {
		return fmt.Errorf("Encrypt: response corrupted in-transit")
	}

	fmt.Fprintf(w, "Encrypted ciphertext: %s", result.Ciphertext)
	return nil
}

Java

要运行此代码，请先设置 Java 开发环境并安装 Cloud KMS Java SDK。

import com.google.cloud.kms.v1.CryptoKeyName;
import com.google.cloud.kms.v1.EncryptResponse;
import com.google.cloud.kms.v1.KeyManagementServiceClient;
import com.google.protobuf.ByteString;
import java.io.IOException;

public class EncryptSymmetric {

  public void encryptSymmetric() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-project-id";
    String locationId = "us-east1";
    String keyRingId = "my-key-ring";
    String keyId = "my-key";
    String plaintext = "Plaintext to encrypt";
    encryptSymmetric(projectId, locationId, keyRingId, keyId, plaintext);
  }

  // Encrypt data with a given key.
  public void encryptSymmetric(
      String projectId, String locationId, String keyRingId, String keyId, String plaintext)
      throws IOException {
    // Initialize client that will be used to send requests. This client only
    // needs to be created once, and can be reused for multiple requests. After
    // completing all of your requests, call the "close" method on the client to
    // safely clean up any remaining background resources.
    try (KeyManagementServiceClient client = KeyManagementServiceClient.create()) {
      // Build the key version name from the project, location, key ring, key,
      // and key version.
      CryptoKeyName keyVersionName = CryptoKeyName.of(projectId, locationId, keyRingId, keyId);

      // Encrypt the plaintext.
      EncryptResponse response = client.encrypt(keyVersionName, ByteString.copyFromUtf8(plaintext));
      System.out.printf("Ciphertext: %s%n", response.getCiphertext().toStringUtf8());
    }
  }
}

Node.js

要运行此代码，请先设置 Node.js 开发环境并安装 Cloud KMS Node.js SDK。

//
// TODO(developer): Uncomment these variables before running the sample.
//
// const projectId = 'my-project';
// const locationId = 'us-east1';
// const keyRingId = 'my-key-ring';
// const keyId = 'my-key';
// const plaintextBuffer = Buffer.from('...');

// Imports the Cloud KMS library
const {KeyManagementServiceClient} = require('@google-cloud/kms');

// Instantiates a client
const client = new KeyManagementServiceClient();

// Build the key name
const keyName = client.cryptoKeyPath(projectId, locationId, keyRingId, keyId);

// Optional, but recommended: compute plaintext's CRC32C.
const crc32c = require('fast-crc32c');
const plaintextCrc32c = crc32c.calculate(plaintextBuffer);

async function encryptSymmetric() {
  const [encryptResponse] = await client.encrypt({
    name: keyName,
    plaintext: plaintextBuffer,
    plaintextCrc32c: {
      value: plaintextCrc32c,
    },
  });

  const ciphertext = encryptResponse.ciphertext;

  // Optional, but recommended: perform integrity verification on encryptResponse.
  // For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
  // https://cloud.google.com/kms/docs/data-integrity-guidelines
  if (!encryptResponse.verifiedPlaintextCrc32c) {
    throw new Error('Encrypt: request corrupted in-transit');
  }
  if (
    crc32c.calculate(ciphertext) !==
    Number(encryptResponse.ciphertextCrc32c.value)
  ) {
    throw new Error('Encrypt: response corrupted in-transit');
  }

  console.log(`Ciphertext: ${ciphertext.toString('base64')}`);
  return ciphertext;
}

return encryptSymmetric();

PHP

如需运行此代码，请先了解如何在 Google Cloud上使用 PHP 并安装 Cloud KMS PHP SDK。

use Google\Cloud\Kms\V1\Client\KeyManagementServiceClient;
use Google\Cloud\Kms\V1\EncryptRequest;

function encrypt_symmetric(
    string $projectId = 'my-project',
    string $locationId = 'us-east1',
    string $keyRingId = 'my-key-ring',
    string $keyId = 'my-key',
    string $plaintext = '...'
) {
    // Create the Cloud KMS client.
    $client = new KeyManagementServiceClient();

    // Build the key name.
    $keyName = $client->cryptoKeyName($projectId, $locationId, $keyRingId, $keyId);

    // Call the API.
    $encryptRequest = (new EncryptRequest())
        ->setName($keyName)
        ->setPlaintext($plaintext);
    $encryptResponse = $client->encrypt($encryptRequest);
    printf('Ciphertext: %s' . PHP_EOL, $encryptResponse->getCiphertext());

    return $encryptResponse;
}

Python

要运行此代码，请先设置 Python 开发环境并安装 Cloud KMS Python SDK。

# Import base64 for printing the ciphertext.
import base64

# Import the client library.
from google.cloud import kms


def encrypt_symmetric(
    project_id: str, location_id: str, key_ring_id: str, key_id: str, plaintext: str
) -> bytes:
    """
    Encrypt plaintext using a symmetric key.

    Args:
        project_id (string): Google Cloud project ID (e.g. 'my-project').
        location_id (string): Cloud KMS location (e.g. 'us-east1').
        key_ring_id (string): ID of the Cloud KMS key ring (e.g. 'my-key-ring').
        key_id (string): ID of the key to use (e.g. 'my-key').
        plaintext (string): message to encrypt

    Returns:
        bytes: Encrypted ciphertext.

    """

    # Convert the plaintext to bytes.
    plaintext_bytes = plaintext.encode("utf-8")

    # Optional, but recommended: compute plaintext's CRC32C.
    # See crc32c() function defined below.
    plaintext_crc32c = crc32c(plaintext_bytes)

    # Create the client.
    client = kms.KeyManagementServiceClient()

    # Build the key name.
    key_name = client.crypto_key_path(project_id, location_id, key_ring_id, key_id)

    # Call the API.
    encrypt_response = client.encrypt(
        request={
            "name": key_name,
            "plaintext": plaintext_bytes,
            "plaintext_crc32c": plaintext_crc32c,
        }
    )

    # Optional, but recommended: perform integrity verification on encrypt_response.
    # For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
    # https://cloud.google.com/kms/docs/data-integrity-guidelines
    if not encrypt_response.verified_plaintext_crc32c:
        raise Exception("The request sent to the server was corrupted in-transit.")
    if not encrypt_response.ciphertext_crc32c == crc32c(encrypt_response.ciphertext):
        raise Exception(
            "The response received from the server was corrupted in-transit."
        )
    # End integrity verification

    print(f"Ciphertext: {base64.b64encode(encrypt_response.ciphertext)}")
    return encrypt_response


def crc32c(data: bytes) -> int:
    """
    Calculates the CRC32C checksum of the provided data.

    Args:
        data: the bytes over which the checksum should be calculated.

    Returns:
        An int representing the CRC32C checksum of the provided bytes.
    """
    import crcmod  # type: ignore

    crc32c_fun = crcmod.predefined.mkPredefinedCrcFun("crc-32c")
    return crc32c_fun(data)

Ruby

要运行此代码，请先设置 Ruby 开发环境并安装 Cloud KMS Ruby SDK。

# TODO(developer): uncomment these values before running the sample.
# project_id  = "my-project"
# location_id = "us-east1"
# key_ring_id = "my-key-ring"
# key_id      = "my-key"
# plaintext  = "..."

# Require the library.
require "google/cloud/kms"

# Create the client.
client = Google::Cloud::Kms.key_management_service

# Build the parent key name.
key_name = client.crypto_key_path project:    project_id,
                                  location:   location_id,
                                  key_ring:   key_ring_id,
                                  crypto_key: key_id

# Call the API.
response = client.encrypt name: key_name, plaintext: plaintext
puts "Ciphertext: #{Base64.strict_encode64 response.ciphertext}"

API

这些示例使用 curl 作为 HTTP 客户端来演示如何使用 API。如需详细了解访问权限控制，请参阅访问 Cloud KMS API。

使用 JSON 和 REST API 时，内容必须先进行 base64 编码，然后才能由 Cloud KMS 加密。

提示：您可以使用 Linux 或 macOS 上的 base64 命令或 Windows 上的 Base64.exe 命令对数据进行 base64 编码或解码。编程语言和脚本语言通常包含用于 base64 编码的库。如需查看命令行示例，请参阅 Cloud Vision API 文档中的 Base64 编码。

要加密数据，请发出 POST 请求并提供相应的项目和密钥信息，并在请求正文的 plaintext 字段中指定要加密的 base64 编码文本。

curl "https://cloudkms.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/keyRings/KEY_RING/cryptoKeys/KEY_NAME:encrypt" \
  --request "POST" \
  --header "authorization: Bearer TOKEN" \
  --header "content-type: application/json" \
  --data "{\"plaintext\": \"PLAINTEXT_TO_ENCRYPT\"}"

替换以下内容：

• PROJECT_ID：包含您要用于加密的密钥环和密钥的项目的 ID。
• LOCATION：包含密钥环的 Cloud KMS 位置。
• KEY_RING：包含您要用于加密的密钥的密钥环。
• KEY_NAME：您要用于加密的密钥的名称。
• PLAINTEXT_TO_ENCRYPT：您要加密的明文数据。在调用 encrypt 方法之前，必须先对明文进行 base64 编码。

以下是包含 base64 编码数据的示例载荷：

{
  "plaintext": "U3VwZXIgc2VjcmV0IHRleHQgdGhhdCBtdXN0IGJlIGVuY3J5cHRlZAo=",
}

停用或安排销毁先前的密钥版本

如果您为了响应可疑突发事件而轮替密钥，重新加密数据后，请停用或安排销毁先前的密钥版本。

停用已启用的密钥版本

只有已启用的密钥版本才能被停用。您可以通过 UpdateCryptoKeyVersion 方法实现这一目的。

控制台

1. 在 Google Cloud 控制台中，前往密钥管理页面。

   前往 Key Management

2. 点击您将停用其密钥版本的密钥所在密钥环的名称。

3. 点击您要停用其密钥版本的密钥。

4. 选中要停用的密钥版本旁边的复选框。

5. 点击标头中的停用。

6. 在确认提示中，点击停用。

gcloud

如需在命令行上使用 Cloud KMS，请先安装或升级到最新版本的 Google Cloud CLI。

gcloud kms keys versions disable key-version \
    --key key \
    --keyring key-ring \
    --location location

将 key-version 替换为要停用的密钥的版本。将 key 替换为密钥的名称。将 key-ring 替换为密钥所在的密钥环的名称。将 location 替换为密钥环的 Cloud KMS 位置。

如需了解所有标志和可能值，请使用 --help 标志运行命令。

C#

要运行此代码，请先设置 C# 开发环境并安装 Cloud KMS C# SDK。

using Google.Cloud.Kms.V1;
using Google.Protobuf.WellKnownTypes;

public class DisableKeyVersionSample
{
    public CryptoKeyVersion DisableKeyVersion(string projectId = "my-project", string locationId = "us-east1", string keyRingId = "my-key-ring", string keyId = "my-key", string keyVersionId = "123")
    {
        // Create the client.
        KeyManagementServiceClient client = KeyManagementServiceClient.Create();

        // Build the key version.
        CryptoKeyVersion keyVersion = new CryptoKeyVersion
        {
            CryptoKeyVersionName = new CryptoKeyVersionName(projectId, locationId, keyRingId, keyId, keyVersionId),
            State = CryptoKeyVersion.Types.CryptoKeyVersionState.Disabled,
        };

        // Build the update mask.
        FieldMask fieldMask = new FieldMask
        {
            Paths = { "state" },
        };

        // Call the API.
        CryptoKeyVersion result = client.UpdateCryptoKeyVersion(keyVersion, fieldMask);

        // Return the result.
        return result;
    }
}

Go

要运行此代码，请先设置 Go 开发环境并安装 Cloud KMS Go SDK。

import (
	"context"
	"fmt"
	"io"

	kms "cloud.google.com/go/kms/apiv1"
	"cloud.google.com/go/kms/apiv1/kmspb"
	fieldmask "google.golang.org/genproto/protobuf/field_mask"
)

// disableKeyVersion disables the specified key version on Cloud KMS.
func disableKeyVersion(w io.Writer, name string) error {
	// name := "projects/my-project/locations/us-east1/keyRings/my-key-ring/cryptoKeys/my-key/cryptoKeyVersions/123"

	// Create the client.
	ctx := context.Background()
	client, err := kms.NewKeyManagementClient(ctx)
	if err != nil {
		return fmt.Errorf("failed to create kms client: %w", err)
	}
	defer client.Close()

	// Build the request.
	req := &kmspb.UpdateCryptoKeyVersionRequest{
		CryptoKeyVersion: &kmspb.CryptoKeyVersion{
			Name:  name,
			State: kmspb.CryptoKeyVersion_DISABLED,
		},
		UpdateMask: &fieldmask.FieldMask{
			Paths: []string{"state"},
		},
	}

	// Call the API.
	result, err := client.UpdateCryptoKeyVersion(ctx, req)
	if err != nil {
		return fmt.Errorf("failed to update key version: %w", err)
	}
	fmt.Fprintf(w, "Disabled key version: %s\n", result)
	return nil
}

Java

要运行此代码，请先设置 Java 开发环境并安装 Cloud KMS Java SDK。

import com.google.cloud.kms.v1.CryptoKeyVersion;
import com.google.cloud.kms.v1.CryptoKeyVersion.CryptoKeyVersionState;
import com.google.cloud.kms.v1.CryptoKeyVersionName;
import com.google.cloud.kms.v1.KeyManagementServiceClient;
import com.google.protobuf.FieldMask;
import com.google.protobuf.util.FieldMaskUtil;
import java.io.IOException;

public class DisableKeyVersion {

  public void disableKeyVersion() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-project-id";
    String locationId = "us-east1";
    String keyRingId = "my-key-ring";
    String keyId = "my-key";
    String keyVersionId = "123";
    disableKeyVersion(projectId, locationId, keyRingId, keyId, keyVersionId);
  }

  // Disable a key version from use.
  public void disableKeyVersion(
      String projectId, String locationId, String keyRingId, String keyId, String keyVersionId)
      throws IOException {
    // Initialize client that will be used to send requests. This client only
    // needs to be created once, and can be reused for multiple requests. After
    // completing all of your requests, call the "close" method on the client to
    // safely clean up any remaining background resources.
    try (KeyManagementServiceClient client = KeyManagementServiceClient.create()) {
      // Build the key version name from the project, location, key ring, key,
      // and key version.
      CryptoKeyVersionName keyVersionName =
          CryptoKeyVersionName.of(projectId, locationId, keyRingId, keyId, keyVersionId);

      // Build the updated key version, setting it to disbaled.
      CryptoKeyVersion keyVersion =
          CryptoKeyVersion.newBuilder()
              .setName(keyVersionName.toString())
              .setState(CryptoKeyVersionState.DISABLED)
              .build();

      // Create a field mask of updated values.
      FieldMask fieldMask = FieldMaskUtil.fromString("state");

      // Disable the key version.
      CryptoKeyVersion response = client.updateCryptoKeyVersion(keyVersion, fieldMask);
      System.out.printf("Disabled key version: %s%n", response.getName());
    }
  }
}

Node.js

要运行此代码，请先设置 Node.js 开发环境并安装 Cloud KMS Node.js SDK。

//
// TODO(developer): Uncomment these variables before running the sample.
//
// const projectId = 'my-project';
// const locationId = 'us-east1';
// const keyRingId = 'my-key-ring';
// const keyId = 'my-key';
// const versionId = '123';

// Imports the Cloud KMS library
const {KeyManagementServiceClient} = require('@google-cloud/kms');

// Instantiates a client
const client = new KeyManagementServiceClient();

// Build the key version name
const versionName = client.cryptoKeyVersionPath(
  projectId,
  locationId,
  keyRingId,
  keyId,
  versionId
);

async function disableKeyVersion() {
  const [version] = await client.updateCryptoKeyVersion({
    cryptoKeyVersion: {
      name: versionName,
      state: 'DISABLED',
    },
    updateMask: {
      paths: ['state'],
    },
  });

  console.log(`Disabled key version: ${version.name}`);
  return version;
}

return disableKeyVersion();

PHP

如需运行此代码，请先了解如何在 Google Cloud上使用 PHP 并安装 Cloud KMS PHP SDK。

use Google\Cloud\Kms\V1\Client\KeyManagementServiceClient;
use Google\Cloud\Kms\V1\CryptoKeyVersion;
use Google\Cloud\Kms\V1\CryptoKeyVersion\CryptoKeyVersionState;
use Google\Cloud\Kms\V1\UpdateCryptoKeyVersionRequest;
use Google\Protobuf\FieldMask;

function disable_key_version(
    string $projectId = 'my-project',
    string $locationId = 'us-east1',
    string $keyRingId = 'my-key-ring',
    string $keyId = 'my-key',
    string $versionId = '123'
): CryptoKeyVersion {
    // Create the Cloud KMS client.
    $client = new KeyManagementServiceClient();

    // Build the key version name.
    $keyVersionName = $client->cryptoKeyVersionName($projectId, $locationId, $keyRingId, $keyId, $versionId);

    // Create the updated version.
    $keyVersion = (new CryptoKeyVersion())
        ->setName($keyVersionName)
        ->setState(CryptoKeyVersionState::DISABLED);

    // Create the field mask.
    $updateMask = (new FieldMask())
        ->setPaths(['state']);

    // Call the API.
    $updateCryptoKeyVersionRequest = (new UpdateCryptoKeyVersionRequest())
        ->setCryptoKeyVersion($keyVersion)
        ->setUpdateMask($updateMask);
    $disabledVersion = $client->updateCryptoKeyVersion($updateCryptoKeyVersionRequest);
    printf('Disabled key version: %s' . PHP_EOL, $disabledVersion->getName());

    return $disabledVersion;
}

Python

要运行此代码，请先设置 Python 开发环境并安装 Cloud KMS Python SDK。

from google.cloud import kms


def disable_key_version(
    project_id: str, location_id: str, key_ring_id: str, key_id: str, version_id: str
) -> kms.CryptoKeyVersion:
    """
    Disable a key.

    Args:
        project_id (string): Google Cloud project ID (e.g. 'my-project').
        location_id (string): Cloud KMS location (e.g. 'us-east1').
        key_ring_id (string): ID of the Cloud KMS key ring (e.g. 'my-key-ring').
        key_id (string): ID of the key to use (e.g. 'my-key').
        version_id (string): ID of the key version to disable (e.g. '1').

    Returns:
        CryptoKeyVersion: The version.

    """

    # Create the client.
    client = kms.KeyManagementServiceClient()

    # Build the key version name.
    key_version_name = client.crypto_key_version_path(
        project_id, location_id, key_ring_id, key_id, version_id
    )

    key_version = {
        "name": key_version_name,
        "state": kms.CryptoKeyVersion.CryptoKeyVersionState.DISABLED,
    }

    # Build the update mask.
    update_mask = {"paths": ["state"]}

    # Call the API.
    disabled_version = client.update_crypto_key_version(
        request={"crypto_key_version": key_version, "update_mask": update_mask}
    )
    print(f"Disabled key version: {disabled_version.name}")
    return disabled_version

Ruby

要运行此代码，请先设置 Ruby 开发环境并安装 Cloud KMS Ruby SDK。

# TODO(developer): uncomment these values before running the sample.
# project_id  = "my-project"
# location_id = "us-east1"
# key_ring_id = "my-key-ring"
# key_id      = "my-key"
# version_id  = "123"

# Require the library.
require "google/cloud/kms"

# Create the client.
client = Google::Cloud::Kms.key_management_service

# Build the key version name.
key_version_name = client.crypto_key_version_path project:            project_id,
                                                  location:           location_id,
                                                  key_ring:           key_ring_id,
                                                  crypto_key:         key_id,
                                                  crypto_key_version: version_id

# Create the updated version.
version = {
  name:  key_version_name,
  state: :DISABLED
}

# Create the field mask.
update_mask = { paths: ["state"] }

# Call the API.
disabled_version = client.update_crypto_key_version crypto_key_version: version, update_mask: update_mask
puts "Disabled key version: #{disabled_version.name}"

安排销毁密钥版本

只有处于已启用或已停用状态的密钥版本可以安排进行销毁。您可以通过 DestroyCryptoKeyVersion 方法实现这一目的。

注意：密钥材料不会立即被销毁。相反，密钥版本会保持已安排销毁状态，直到达到配置的已安排销毁时长。在此期限结束后，密钥材料会自动销毁。这一安全备用方案不可替换。

如果您决定不进行销毁，可以恢复密钥版本。不过，在配置的预定销毁时长过后，销毁操作无法撤消。使用此密钥版本加密的任何数据都无法解密。

控制台

1. 在 Google Cloud 控制台中，前往密钥管理页面。

   前往 Key Management

2. 选中要安排销毁的密钥版本旁边的复选框。

3. 点击标头中的销毁。

4. 在确认提示中输入密钥名称，然后点击安排销毁。

gcloud

如需在命令行上使用 Cloud KMS，请先安装或升级到最新版本的 Google Cloud CLI。

gcloud kms keys versions destroy KEY_VERSION \
    --key KEY_NAME \
    --keyring KEY_RING \
    --location LOCATION

替换以下内容：

• KEY_VERSION：您要销毁的密钥版本的数量。
• KEY_NAME：包含您要销毁的密钥版本的密钥的名称。
• KEY_RING：包含您要销毁的密钥版本的密钥环的名称。
• LOCATION：包含您要销毁的密钥版本的密钥环的位置。

如需了解所有标志和可能值，请使用 --help 标志运行命令。

C#

要运行此代码，请先设置 C# 开发环境并安装 Cloud KMS C# SDK。

using Google.Cloud.Kms.V1;

public class DestroyKeyVersionSample
{
    public CryptoKeyVersion DestroyKeyVersion(
      string projectId = "my-project", string locationId = "us-east1", string keyRingId = "my-key-ring", string keyId = "my-key", string keyVersionId = "123")
    {
        // Create the client.
        KeyManagementServiceClient client = KeyManagementServiceClient.Create();

        // Build the key version name.
        CryptoKeyVersionName keyVersionName = new CryptoKeyVersionName(projectId, locationId, keyRingId, keyId, keyVersionId);

        // Call the API.
        CryptoKeyVersion result = client.DestroyCryptoKeyVersion(keyVersionName);

        // Return the result.
        return result;
    }
}

Go

要运行此代码，请先设置 Go 开发环境并安装 Cloud KMS Go SDK。

import (
	"context"
	"fmt"
	"io"

	kms "cloud.google.com/go/kms/apiv1"
	"cloud.google.com/go/kms/apiv1/kmspb"
)

// destroyKeyVersion marks a specified key version for deletion. The key can be
// restored if requested within 24 hours.
func destroyKeyVersion(w io.Writer, name string) error {
	// name := "projects/my-project/locations/us-east1/keyRings/my-key-ring/cryptoKeys/my-key/cryptoKeyVersions/123"

	// Create the client.
	ctx := context.Background()
	client, err := kms.NewKeyManagementClient(ctx)
	if err != nil {
		return fmt.Errorf("failed to create kms client: %w", err)
	}
	defer client.Close()

	// Build the request.
	req := &kmspb.DestroyCryptoKeyVersionRequest{
		Name: name,
	}

	// Call the API.
	result, err := client.DestroyCryptoKeyVersion(ctx, req)
	if err != nil {
		return fmt.Errorf("failed to destroy key version: %w", err)
	}
	fmt.Fprintf(w, "Destroyed key version: %s\n", result)
	return nil
}

Java

要运行此代码，请先设置 Java 开发环境并安装 Cloud KMS Java SDK。

import com.google.cloud.kms.v1.CryptoKeyVersion;
import com.google.cloud.kms.v1.CryptoKeyVersionName;
import com.google.cloud.kms.v1.KeyManagementServiceClient;
import java.io.IOException;

public class DestroyKeyVersion {

  public void destroyKeyVersion() throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    String projectId = "your-project-id";
    String locationId = "us-east1";
    String keyRingId = "my-key-ring";
    String keyId = "my-key";
    String keyVersionId = "123";
    destroyKeyVersion(projectId, locationId, keyRingId, keyId, keyVersionId);
  }

  // Schedule destruction of the given key version.
  public void destroyKeyVersion(
      String projectId, String locationId, String keyRingId, String keyId, String keyVersionId)
      throws IOException {
    // Initialize client that will be used to send requests. This client only
    // needs to be created once, and can be reused for multiple requests. After
    // completing all of your requests, call the "close" method on the client to
    // safely clean up any remaining background resources.
    try (KeyManagementServiceClient client = KeyManagementServiceClient.create()) {
      // Build the key version name from the project, location, key ring, key,
      // and key version.
      CryptoKeyVersionName keyVersionName =
          CryptoKeyVersionName.of(projectId, locationId, keyRingId, keyId, keyVersionId);

      // Destroy the key version.
      CryptoKeyVersion response = client.destroyCryptoKeyVersion(keyVersionName);
      System.out.printf("Destroyed key version: %s%n", response.getName());
    }
  }
}

Node.js

要运行此代码，请先设置 Node.js 开发环境并安装 Cloud KMS Node.js SDK。

//
// TODO(developer): Uncomment these variables before running the sample.
//
// const projectId = 'my-project';
// const locationId = 'us-east1';
// const keyRingId = 'my-key-ring';
// const keyId = 'my-key';
// const versionId = '123';

// Imports the Cloud KMS library
const {KeyManagementServiceClient} = require('@google-cloud/kms');

// Instantiates a client
const client = new KeyManagementServiceClient();

// Build the key version name
const versionName = client.cryptoKeyVersionPath(
  projectId,
  locationId,
  keyRingId,
  keyId,
  versionId
);

async function destroyKeyVersion() {
  const [version] = await client.destroyCryptoKeyVersion({
    name: versionName,
  });

  console.log(`Destroyed key version: ${version.name}`);
  return version;
}

return destroyKeyVersion();

PHP

如需运行此代码，请先了解如何在 Google Cloud上使用 PHP 并安装 Cloud KMS PHP SDK。

use Google\Cloud\Kms\V1\Client\KeyManagementServiceClient;
use Google\Cloud\Kms\V1\DestroyCryptoKeyVersionRequest;

function destroy_key_version(
    string $projectId = 'my-project',
    string $locationId = 'us-east1',
    string $keyRingId = 'my-key-ring',
    string $keyId = 'my-key',
    string $versionId = '123'
) {
    // Create the Cloud KMS client.
    $client = new KeyManagementServiceClient();

    // Build the key version name.
    $keyVersionName = $client->cryptoKeyVersionName($projectId, $locationId, $keyRingId, $keyId, $versionId);

    // Call the API.
    $destroyCryptoKeyVersionRequest = (new DestroyCryptoKeyVersionRequest())
        ->setName($keyVersionName);
    $destroyedVersion = $client->destroyCryptoKeyVersion($destroyCryptoKeyVersionRequest);
    printf('Destroyed key version: %s' . PHP_EOL, $destroyedVersion->getName());

    return $destroyedVersion;
}

Python

要运行此代码，请先设置 Python 开发环境并安装 Cloud KMS Python SDK。

from google.cloud import kms


def destroy_key_version(
    project_id: str, location_id: str, key_ring_id: str, key_id: str, version_id: str
) -> kms.CryptoKeyVersion:
    """
    Schedule destruction of the given key version.

    Args:
        project_id (string): Google Cloud project ID (e.g. 'my-project').
        location_id (string): Cloud KMS location (e.g. 'us-east1').
        key_ring_id (string): ID of the Cloud KMS key ring (e.g. 'my-key-ring').
        key_id (string): ID of the key to use (e.g. 'my-key').
        version_id (string): ID of the key version to destroy (e.g. '1').

    Returns:
        CryptoKeyVersion: The version.

    """

    # Create the client.
    client = kms.KeyManagementServiceClient()

    # Build the key version name.
    key_version_name = client.crypto_key_version_path(
        project_id, location_id, key_ring_id, key_id, version_id
    )

    # Call the API.
    destroyed_version = client.destroy_crypto_key_version(
        request={"name": key_version_name}
    )
    print(f"Destroyed key version: {destroyed_version.name}")
    return destroyed_version

Ruby

要运行此代码，请先设置 Ruby 开发环境并安装 Cloud KMS Ruby SDK。

# TODO(developer): uncomment these values before running the sample.
# project_id  = "my-project"
# location_id = "us-east1"
# key_ring_id = "my-key-ring"
# key_id      = "my-key"
# version_id  = "123"

# Require the library.
require "google/cloud/kms"

# Create the client.
client = Google::Cloud::Kms.key_management_service

# Build the key version name.
key_version_name = client.crypto_key_version_path project:            project_id,
                                                  location:           location_id,
                                                  key_ring:           key_ring_id,
                                                  crypto_key:         key_id,
                                                  crypto_key_version: version_id

# Call the API.
destroyed_version = client.destroy_crypto_key_version name: key_version_name
puts "Destroyed key version: #{destroyed_version.name}"

API

这些示例使用 curl 作为 HTTP 客户端来演示如何使用 API。如需详细了解访问权限控制，请参阅访问 Cloud KMS API。

通过调用 CryptoKeyVersions.destroy 方法销毁密钥版本。

curl "https://cloudkms.googleapis.com/v1/projects/PROJECT_ID/locations/LOCATION/keyRings/KEY_RING/cryptoKeys/KEY_NAME/cryptoKeyVersions/KEY_VERSION:destroy" \
    --request "POST" \
    --header "authorization: Bearer TOKEN"

替换以下内容：

• PROJECT_ID：包含您要销毁的密钥版本的项目的标识符。
• LOCATION：包含您要销毁的密钥版本的密钥环的位置。
• KEY_RING：包含您要销毁的密钥版本的密钥环的名称。
• KEY_NAME：包含您要销毁的密钥版本的密钥的名称。
• KEY_VERSION：您要销毁的密钥版本的数量。