1 files changed, 349 insertions, 0 deletions
diff --git a/weed/kms/gcp/gcp_kms.go b/weed/kms/gcp/gcp_kms.go
new file mode 100644
index 000000000..5380a7aeb
--- /dev/null
+++ b/weed/kms/gcp/gcp_kms.go
@@ -0,0 +1,349 @@
+package gcp
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"strings"
+	"time"
+
+	"google.golang.org/api/option"
+
+	kms "cloud.google.com/go/kms/apiv1"
+	"cloud.google.com/go/kms/apiv1/kmspb"
+
+	"github.com/seaweedfs/seaweedfs/weed/glog"
+	seaweedkms "github.com/seaweedfs/seaweedfs/weed/kms"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+)
+
+func init() {
+	// Register the Google Cloud KMS provider
+	seaweedkms.RegisterProvider("gcp", NewGCPKMSProvider)
+}
+
+// GCPKMSProvider implements the KMSProvider interface using Google Cloud KMS
+type GCPKMSProvider struct {
+	client    *kms.KeyManagementClient
+	projectID string
+}
+
+// GCPKMSConfig contains configuration for the Google Cloud KMS provider
+type GCPKMSConfig struct {
+	ProjectID             string `json:"project_id"`              // GCP project ID
+	CredentialsFile       string `json:"credentials_file"`        // Path to service account JSON file
+	CredentialsJSON       string `json:"credentials_json"`        // Service account JSON content (base64 encoded)
+	UseDefaultCredentials bool   `json:"use_default_credentials"` // Use default GCP credentials (metadata service, gcloud, etc.)
+	RequestTimeout        int    `json:"request_timeout"`         // Request timeout in seconds (default: 30)
+}
+
+// NewGCPKMSProvider creates a new Google Cloud KMS provider
+func NewGCPKMSProvider(config util.Configuration) (seaweedkms.KMSProvider, error) {
+	if config == nil {
+		return nil, fmt.Errorf("Google Cloud KMS configuration is required")
+	}
+
+	// Extract configuration
+	projectID := config.GetString("project_id")
+	if projectID == "" {
+		return nil, fmt.Errorf("project_id is required for Google Cloud KMS provider")
+	}
+
+	credentialsFile := config.GetString("credentials_file")
+	credentialsJSON := config.GetString("credentials_json")
+	useDefaultCredentials := config.GetBool("use_default_credentials")
+
+	requestTimeout := config.GetInt("request_timeout")
+	if requestTimeout == 0 {
+		requestTimeout = 30 // Default 30 seconds
+	}
+
+	// Prepare client options
+	var clientOptions []option.ClientOption
+
+	// Configure credentials
+	if credentialsFile != "" {
+		clientOptions = append(clientOptions, option.WithCredentialsFile(credentialsFile))
+		glog.V(1).Infof("GCP KMS: Using credentials file %s", credentialsFile)
+	} else if credentialsJSON != "" {
+		// Decode base64 credentials if provided
+		credBytes, err := base64.StdEncoding.DecodeString(credentialsJSON)
+		if err != nil {
+			return nil, fmt.Errorf("failed to decode credentials JSON: %w", err)
+		}
+		clientOptions = append(clientOptions, option.WithCredentialsJSON(credBytes))
+		glog.V(1).Infof("GCP KMS: Using provided credentials JSON")
+	} else if !useDefaultCredentials {
+		return nil, fmt.Errorf("either credentials_file, credentials_json, or use_default_credentials=true must be provided")
+	} else {
+		glog.V(1).Infof("GCP KMS: Using default credentials")
+	}
+
+	// Set request timeout
+	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(requestTimeout)*time.Second)
+	defer cancel()
+
+	// Create KMS client
+	client, err := kms.NewKeyManagementClient(ctx, clientOptions...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create Google Cloud KMS client: %w", err)
+	}
+
+	provider := &GCPKMSProvider{
+		client:    client,
+		projectID: projectID,
+	}
+
+	glog.V(1).Infof("Google Cloud KMS provider initialized for project %s", projectID)
+	return provider, nil
+}
+
+// GenerateDataKey generates a new data encryption key using Google Cloud KMS
+func (p *GCPKMSProvider) GenerateDataKey(ctx context.Context, req *seaweedkms.GenerateDataKeyRequest) (*seaweedkms.GenerateDataKeyResponse, error) {
+	if req == nil {
+		return nil, fmt.Errorf("GenerateDataKeyRequest cannot be nil")
+	}
+
+	if req.KeyID == "" {
+		return nil, fmt.Errorf("KeyID is required")
+	}
+
+	// Validate key spec
+	var keySize int
+	switch req.KeySpec {
+	case seaweedkms.KeySpecAES256:
+		keySize = 32 // 256 bits
+	default:
+		return nil, fmt.Errorf("unsupported key spec: %s", req.KeySpec)
+	}
+
+	// Generate data key locally (GCP KMS doesn't have GenerateDataKey like AWS)
+	dataKey := make([]byte, keySize)
+	if _, err := rand.Read(dataKey); err != nil {
+		return nil, fmt.Errorf("failed to generate random data key: %w", err)
+	}
+
+	// Encrypt the data key using GCP KMS
+	glog.V(4).Infof("GCP KMS: Encrypting data key using key %s", req.KeyID)
+
+	// Build the encryption request
+	encryptReq := &kmspb.EncryptRequest{
+		Name:      req.KeyID,
+		Plaintext: dataKey,
+	}
+
+	// Add additional authenticated data from encryption context
+	if len(req.EncryptionContext) > 0 {
+		// Convert encryption context to additional authenticated data
+		aad := p.encryptionContextToAAD(req.EncryptionContext)
+		encryptReq.AdditionalAuthenticatedData = []byte(aad)
+	}
+
+	// Call GCP KMS to encrypt the data key
+	encryptResp, err := p.client.Encrypt(ctx, encryptReq)
+	if err != nil {
+		return nil, p.convertGCPError(err, req.KeyID)
+	}
+
+	// Create standardized envelope format for consistent API behavior
+	envelopeBlob, err := seaweedkms.CreateEnvelope("gcp", encryptResp.Name, string(encryptResp.Ciphertext), nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create ciphertext envelope: %w", err)
+	}
+
+	response := &seaweedkms.GenerateDataKeyResponse{
+		KeyID:          encryptResp.Name, // GCP returns the full resource name
+		Plaintext:      dataKey,
+		CiphertextBlob: envelopeBlob, // Store in standardized envelope format
+	}
+
+	glog.V(4).Infof("GCP KMS: Generated and encrypted data key using key %s", req.KeyID)
+	return response, nil
+}
+
+// Decrypt decrypts an encrypted data key using Google Cloud KMS
+func (p *GCPKMSProvider) Decrypt(ctx context.Context, req *seaweedkms.DecryptRequest) (*seaweedkms.DecryptResponse, error) {
+	if req == nil {
+		return nil, fmt.Errorf("DecryptRequest cannot be nil")
+	}
+
+	if len(req.CiphertextBlob) == 0 {
+		return nil, fmt.Errorf("CiphertextBlob cannot be empty")
+	}
+
+	// Parse the ciphertext envelope to extract key information
+	envelope, err := seaweedkms.ParseEnvelope(req.CiphertextBlob)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse ciphertext envelope: %w", err)
+	}
+
+	keyName := envelope.KeyID
+	if keyName == "" {
+		return nil, fmt.Errorf("envelope missing key ID")
+	}
+
+	// Convert string back to bytes
+	ciphertext := []byte(envelope.Ciphertext)
+
+	// Build the decryption request
+	decryptReq := &kmspb.DecryptRequest{
+		Name:       keyName,
+		Ciphertext: ciphertext,
+	}
+
+	// Add additional authenticated data from encryption context
+	if len(req.EncryptionContext) > 0 {
+		aad := p.encryptionContextToAAD(req.EncryptionContext)
+		decryptReq.AdditionalAuthenticatedData = []byte(aad)
+	}
+
+	// Call GCP KMS to decrypt the data key
+	glog.V(4).Infof("GCP KMS: Decrypting data key using key %s", keyName)
+	decryptResp, err := p.client.Decrypt(ctx, decryptReq)
+	if err != nil {
+		return nil, p.convertGCPError(err, keyName)
+	}
+
+	response := &seaweedkms.DecryptResponse{
+		KeyID:     keyName,
+		Plaintext: decryptResp.Plaintext,
+	}
+
+	glog.V(4).Infof("GCP KMS: Decrypted data key using key %s", keyName)
+	return response, nil
+}
+
+// DescribeKey validates that a key exists and returns its metadata
+func (p *GCPKMSProvider) DescribeKey(ctx context.Context, req *seaweedkms.DescribeKeyRequest) (*seaweedkms.DescribeKeyResponse, error) {
+	if req == nil {
+		return nil, fmt.Errorf("DescribeKeyRequest cannot be nil")
+	}
+
+	if req.KeyID == "" {
+		return nil, fmt.Errorf("KeyID is required")
+	}
+
+	// Build the request to get the crypto key
+	getKeyReq := &kmspb.GetCryptoKeyRequest{
+		Name: req.KeyID,
+	}
+
+	// Call GCP KMS to get key information
+	glog.V(4).Infof("GCP KMS: Describing key %s", req.KeyID)
+	key, err := p.client.GetCryptoKey(ctx, getKeyReq)
+	if err != nil {
+		return nil, p.convertGCPError(err, req.KeyID)
+	}
+
+	response := &seaweedkms.DescribeKeyResponse{
+		KeyID:       key.Name,
+		ARN:         key.Name, // GCP uses resource names instead of ARNs
+		Description: "Google Cloud KMS key",
+	}
+
+	// Map GCP key purpose to our usage enum
+	if key.Purpose == kmspb.CryptoKey_ENCRYPT_DECRYPT {
+		response.KeyUsage = seaweedkms.KeyUsageEncryptDecrypt
+	}
+
+	// Map GCP key state to our state enum
+	// Get the primary version to check its state
+	if key.Primary != nil && key.Primary.State == kmspb.CryptoKeyVersion_ENABLED {
+		response.KeyState = seaweedkms.KeyStateEnabled
+	} else {
+		response.KeyState = seaweedkms.KeyStateDisabled
+	}
+
+	// GCP KMS keys are managed by Google Cloud
+	response.Origin = seaweedkms.KeyOriginGCP
+
+	glog.V(4).Infof("GCP KMS: Described key %s (state: %s)", req.KeyID, response.KeyState)
+	return response, nil
+}
+
+// GetKeyID resolves a key name to the full resource name
+func (p *GCPKMSProvider) GetKeyID(ctx context.Context, keyIdentifier string) (string, error) {
+	if keyIdentifier == "" {
+		return "", fmt.Errorf("key identifier cannot be empty")
+	}
+
+	// If it's already a full resource name, return as-is
+	if strings.HasPrefix(keyIdentifier, "projects/") {
+		return keyIdentifier, nil
+	}
+
+	// Otherwise, try to construct the full resource name or validate via DescribeKey
+	descReq := &seaweedkms.DescribeKeyRequest{KeyID: keyIdentifier}
+	descResp, err := p.DescribeKey(ctx, descReq)
+	if err != nil {
+		return "", fmt.Errorf("failed to resolve key identifier %s: %w", keyIdentifier, err)
+	}
+
+	return descResp.KeyID, nil
+}
+
+// Close cleans up any resources used by the provider
+func (p *GCPKMSProvider) Close() error {
+	if p.client != nil {
+		err := p.client.Close()
+		if err != nil {
+			glog.Errorf("Error closing GCP KMS client: %v", err)
+			return err
+		}
+	}
+	glog.V(2).Infof("Google Cloud KMS provider closed")
+	return nil
+}
+
+// encryptionContextToAAD converts encryption context map to additional authenticated data
+// This is a simplified implementation - in production, you might want a more robust serialization
+func (p *GCPKMSProvider) encryptionContextToAAD(context map[string]string) string {
+	if len(context) == 0 {
+		return ""
+	}
+
+	// Simple key=value&key=value format
+	var parts []string
+	for k, v := range context {
+		parts = append(parts, fmt.Sprintf("%s=%s", k, v))
+	}
+	return strings.Join(parts, "&")
+}
+
+// convertGCPError converts Google Cloud KMS errors to our standard KMS errors
+func (p *GCPKMSProvider) convertGCPError(err error, keyID string) error {
+	// Google Cloud SDK uses gRPC status codes
+	errMsg := err.Error()
+
+	if strings.Contains(errMsg, "not found") || strings.Contains(errMsg, "NotFound") {
+		return &seaweedkms.KMSError{
+			Code:    seaweedkms.ErrCodeNotFoundException,
+			Message: fmt.Sprintf("Key not found in Google Cloud KMS: %v", err),
+			KeyID:   keyID,
+		}
+	}
+
+	if strings.Contains(errMsg, "permission") || strings.Contains(errMsg, "access") || strings.Contains(errMsg, "Forbidden") {
+		return &seaweedkms.KMSError{
+			Code:    seaweedkms.ErrCodeAccessDenied,
+			Message: fmt.Sprintf("Access denied to Google Cloud KMS: %v", err),
+			KeyID:   keyID,
+		}
+	}
+
+	if strings.Contains(errMsg, "disabled") || strings.Contains(errMsg, "unavailable") {
+		return &seaweedkms.KMSError{
+			Code:    seaweedkms.ErrCodeKeyUnavailable,
+			Message: fmt.Sprintf("Key unavailable in Google Cloud KMS: %v", err),
+			KeyID:   keyID,
+		}
+	}
+
+	// For unknown errors, wrap as internal failure
+	return &seaweedkms.KMSError{
+		Code:    seaweedkms.ErrCodeKMSInternalFailure,
+		Message: fmt.Sprintf("Google Cloud KMS error: %v", err),
+		KeyID:   keyID,
+	}
+}