allow S3 gateway to support object locked buckets (#13257)

- Supports object locked buckets that require
  PutObject() to set content-md5 always.
- Use SSE-S3 when S3 gateway is being used instead
  of SSE-KMS for auto-encryption.

cmd/bucket-encryption.go

@@ -21,7 +21,7 @@ import (
 	"errors"
 	"io"
 
-	bucketsse "github.com/minio/minio/internal/bucket/encryption"
+	sse "github.com/minio/minio/internal/bucket/encryption"
 )
 
 // BucketSSEConfigSys - in-memory cache of bucket encryption config
@@ -33,7 +33,7 @@ func NewBucketSSEConfigSys() *BucketSSEConfigSys {
 }
 
 // Get - gets bucket encryption config for the given bucket.
-func (sys *BucketSSEConfigSys) Get(bucket string) (*bucketsse.BucketSSEConfig, error) {
+func (sys *BucketSSEConfigSys) Get(bucket string) (*sse.BucketSSEConfig, error) {
 	if globalIsGateway {
 		objAPI := newObjectLayerFn()
 		if objAPI == nil {
@@ -47,8 +47,8 @@ func (sys *BucketSSEConfigSys) Get(bucket string) (*bucketsse.BucketSSEConfig, e
 }
 
 // validateBucketSSEConfig parses bucket encryption configuration and validates if it is supported by MinIO.
-func validateBucketSSEConfig(r io.Reader) (*bucketsse.BucketSSEConfig, error) {
-	encConfig, err := bucketsse.ParseBucketSSEConfig(r)
+func validateBucketSSEConfig(r io.Reader) (*sse.BucketSSEConfig, error) {
+	encConfig, err := sse.ParseBucketSSEConfig(r)
 	if err != nil {
 		return nil, err
 	}

cmd/bucket-handlers.go

@@ -39,6 +39,7 @@ import (
 
 	"github.com/minio/minio-go/v7/pkg/set"
 	"github.com/minio/minio-go/v7/pkg/tags"
+	sse "github.com/minio/minio/internal/bucket/encryption"
 	objectlock "github.com/minio/minio/internal/bucket/object/lock"
 	"github.com/minio/minio/internal/bucket/replication"
 	"github.com/minio/minio/internal/config/dns"
@@ -976,7 +977,10 @@ func (api objectAPIHandlers) PostPolicyBucketHandler(w http.ResponseWriter, r *h
 
 	// Check if bucket encryption is enabled
 	sseConfig, _ := globalBucketSSEConfigSys.Get(bucket)
-	sseConfig.Apply(r.Header, globalAutoEncryption)
+	sseConfig.Apply(r.Header, sse.ApplyOptions{
+		AutoEncrypt: globalAutoEncryption,
+		Passthrough: globalIsGateway && globalGatewayName == S3BackendGateway,
+	})
 
 	// get gateway encryption options
 	var opts ObjectOptions

cmd/bucket-lifecycle.go

@@ -380,9 +380,9 @@ const (
 
 // Encryption specifies encryption setting on restored bucket
 type Encryption struct {
-	EncryptionType sse.SSEAlgorithm `xml:"EncryptionType"`
-	KMSContext     string           `xml:"KMSContext,omitempty"`
-	KMSKeyID       string           `xml:"KMSKeyId,omitempty"`
+	EncryptionType sse.Algorithm `xml:"EncryptionType"`
+	KMSContext     string        `xml:"KMSContext,omitempty"`
+	KMSKeyID       string        `xml:"KMSKeyId,omitempty"`
 }
 
 // MetadataEntry denotes name and value.

cmd/gateway/s3/gateway-s3.go

@@ -481,6 +481,10 @@ func (l *s3Objects) PutObject(ctx context.Context, bucket string, object string,
 		UserMetadata:         opts.UserDefined,
 		ServerSideEncryption: opts.ServerSideEncryption,
 		UserTags:             tagMap,
+		// Content-Md5 is needed for buckets with object locking,
+		// instead of spending an extra API call to detect this
+		// we can set md5sum to be calculated always.
+		SendContentMd5: true,
 	}
 	ui, err := l.Client.PutObject(ctx, bucket, object, data, data.Size(), data.MD5Base64String(), data.SHA256HexString(), putOpts)
 	if err != nil {

cmd/object-handlers.go

@@ -41,6 +41,7 @@ import (
 	"github.com/minio/minio-go/v7/pkg/credentials"
 	"github.com/minio/minio-go/v7/pkg/encrypt"
 	"github.com/minio/minio-go/v7/pkg/tags"
+	sse "github.com/minio/minio/internal/bucket/encryption"
 	"github.com/minio/minio/internal/bucket/lifecycle"
 	objectlock "github.com/minio/minio/internal/bucket/object/lock"
 	"github.com/minio/minio/internal/bucket/replication"
@@ -997,7 +998,10 @@ func (api objectAPIHandlers) CopyObjectHandler(w http.ResponseWriter, r *http.Re
 
 	// Check if bucket encryption is enabled
 	sseConfig, _ := globalBucketSSEConfigSys.Get(dstBucket)
-	sseConfig.Apply(r.Header, globalAutoEncryption)
+	sseConfig.Apply(r.Header, sse.ApplyOptions{
+		AutoEncrypt: globalAutoEncryption,
+		Passthrough: globalIsGateway && globalGatewayName == S3BackendGateway,
+	})
 
 	var srcOpts, dstOpts ObjectOptions
 	srcOpts, err = copySrcOpts(ctx, r, srcBucket, srcObject)
@@ -1667,7 +1671,10 @@ func (api objectAPIHandlers) PutObjectHandler(w http.ResponseWriter, r *http.Req
 
 	// Check if bucket encryption is enabled
 	sseConfig, _ := globalBucketSSEConfigSys.Get(bucket)
-	sseConfig.Apply(r.Header, globalAutoEncryption)
+	sseConfig.Apply(r.Header, sse.ApplyOptions{
+		AutoEncrypt: globalAutoEncryption,
+		Passthrough: globalIsGateway && globalGatewayName == S3BackendGateway,
+	})
 
 	actualSize := size
 	if objectAPI.IsCompressionSupported() && isCompressible(r.Header, object) && size > 0 {
@@ -1990,7 +1997,10 @@ func (api objectAPIHandlers) PutObjectExtractHandler(w http.ResponseWriter, r *h
 
 	// Check if bucket encryption is enabled
 	sseConfig, _ := globalBucketSSEConfigSys.Get(bucket)
-	sseConfig.Apply(r.Header, globalAutoEncryption)
+	sseConfig.Apply(r.Header, sse.ApplyOptions{
+		AutoEncrypt: globalAutoEncryption,
+		Passthrough: globalIsGateway && globalGatewayName == S3BackendGateway,
+	})
 
 	retPerms := isPutActionAllowed(ctx, getRequestAuthType(r), bucket, object, r, iampolicy.PutObjectRetentionAction)
 	holdPerms := isPutActionAllowed(ctx, getRequestAuthType(r), bucket, object, r, iampolicy.PutObjectLegalHoldAction)
@@ -2186,7 +2196,10 @@ func (api objectAPIHandlers) NewMultipartUploadHandler(w http.ResponseWriter, r
 
 	// Check if bucket encryption is enabled
 	sseConfig, _ := globalBucketSSEConfigSys.Get(bucket)
-	sseConfig.Apply(r.Header, globalAutoEncryption)
+	sseConfig.Apply(r.Header, sse.ApplyOptions{
+		AutoEncrypt: globalAutoEncryption,
+		Passthrough: globalIsGateway && globalGatewayName == S3BackendGateway,
+	})
 
 	// Validate storage class metadata if present
 	if sc := r.Header.Get(xhttp.AmzStorageClass); sc != "" {